What's the most original intersection/interchange you've ever seen?

[jakeroot]

I've always found the interchange between I-476 and PA 3 in Broomall, PA to be a tad bit peculiar (though it doesn't nearly compare to the other ones posted in the thread). It's a perfect diamond interchange with one cloverleaf ramp for PA 3 west to I-476 south. Traffic can't turn left at the traffic signal beyond the cloverleaf ramp (nor can they turn right from the opposite direction), yet there's marked and usable pavement for motorists to use if they choose to make the illegal left or right. This small ramp connecting PA 3 to the ramp from 3 east to 476 south is only legally allowed to be used by traffic coming off of I-476 south on the offramp, which even has it's own designated lane as you approach the intersection. Forgive me if there are a bunch of other examples of this same situation, but I thought it was interesting.

This setup is used, almost always, for two reasons:

1) Transit stops on the ramps, thus permitting re-entry for buses
2) re-entry for overheight vehicles unable to use the freeway underpass

EDIT: Your example is definitely for reason 2.

There's one A4 in Olympia, WA that continues to baffle me. Unlike the two primary uses for the re-entry ramp listed above, this ramp has neither of those obstacles (the freeway uses an overpass, and there's no transit stops). The ramp exists only for traffic that took the wrong exit:

[CtrlAltDel]

Indiana Toll Road/I-65/US 12/US 20/Assorted local roads: https://www.google.com/maps/@41.5916701,-87.305009,2705m/data=!3m1!1e3

This is the only place I've ever seen where a ramp is a 540 degree turn. It goes from I-65 north, then east under the Toll Road, then south along it, back west over the Toll Road, into the loop ramp of a trumpet, and finally onto the Toll Road eastbound.

Is it weird that that way avoids the toll booths? I can't help but think that the people getting on the Toll Road aren't getting their entrance ticket.

[theline]

Indiana Toll Road/I-65/US 12/US 20/Assorted local roads: https://www.google.com/maps/@41.5916701,-87.305009,2705m/data=!3m1!1e3

This is the only place I've ever seen where a ramp is a 540 degree turn. It goes from I-65 north, then east under the Toll Road, then south along it, back west over the Toll Road, into the loop ramp of a trumpet, and finally onto the Toll Road eastbound.

Is it weird that that way avoids the toll booths? I can't help but think that the people getting on the Toll Road aren't getting their entrance ticket.

That part of the ITR is not ticketed. The barrier for tickets is just east of the Borman exit, about MM 22 I think. From that barrier to the Illinois line, there are just occasional stops for tolls. In fact, motorists can travel between I-65 and I-94 without paying a toll.

[cpzilliacus]

In the Fairland area of Montgomery County, Maryland is the interchange of U.S. 29 (Columbia Pike) and Md. 200 (ICC toll road).

It features: 

• Two soaring flyovers crossing the middle of the interchange to carry Md. 200 eastbound to U.S. 29 northbound and Md. 200 westbound to U.S. 29 southbound;
• A cloverleaf ramp to carry southbound U.S. 29 traffic onto Md. 200 eastbound which passes over the ramp that carries traffic from eastbound Md. 200 to southbound U.S. 29 - twice - and passes under both of the flyover ramps;
• A cloverleaf ramp to carry eastbound Md. 200 traffic to Briggs Chaney Road (it has a separate exit number);
• A jughandle ramp to carry southbound U.S. 29 traffic to Fairland Road;  and
• A multi-purpose trail that runs north and south parallel to U.S. 29 under much of this interchange.

It was built this way in part because of the extremely constrained amount of space available. Land was set aside for the interchange many decades ago, and I believe it was assumed that a cloverleaf-type of interchange would be built here.

[paulthemapguy]

This setup is used, almost always, for two reasons:

1) Transit stops on the ramps, thus permitting re-entry for buses
2) re-entry for overheight vehicles unable to use the freeway underpass

EDIT: Your example is definitely for reason 2.

There's one A4 in Olympia, WA that continues to baffle me. Unlike the two primary uses for the re-entry ramp listed above, this ramp has neither of those obstacles (the freeway uses an overpass, and there's no transit stops). The ramp exists only for traffic that took the wrong exit:

I think it's actually quite common seeing straight lanes on exit ramps for parclos and diamond interchanges.  But if an over-height vehicle can be restricted from an underpass, we can also consider that an overweight vehicle can be too heavy for an overpass with a weight restriction.  Weight restrictions are usually only posted if they're below the typical maxima dictated in the state law.  For vehicles with exceeding weights, you have to analyze it bridge-by-bridge sometimes.

[empirestate]

Also from MA, the quadruple trumpet in West Springfield. 2 major expressways, neither of which terminate at the interchange, plus US 5. Straight out of the "only in Massachusetts" category. They finally striped it for 2 lanes during the last repaving project, so it isn't as much of a charlie foxtrot as it once was, but it is still bad. Good luck finding another quadruple trumpet.

Years ago I pointed out that interchange as special or confusing on m.t.r. and a couple of people actually responded that it's "just" a trumpet interchange.  *sigh*

Wow, that's a lot of trumpets! 

Guess we'll have to start calling that the John Williams Interchange.

[CobaltYoshi27]

Also from MA, the quadruple trumpet in West Springfield. 2 major expressways, neither of which terminate at the interchange, plus US 5. Straight out of the "only in Massachusetts" category. They finally striped it for 2 lanes during the last repaving project, so it isn't as much of a charlie foxtrot as it once was, but it is still bad. Good luck finding another quadruple trumpet.

Years ago I pointed out that interchange as special or confusing on m.t.r. and a couple of people actually responded that it's "just" a trumpet interchange.  *sigh*

Wow, that's a lot of trumpets! 

Guess we'll have to start calling that the John Williams Interchange.

I GET IT. 10/10

[Rothman]

Also from MA, the quadruple trumpet in West Springfield. 2 major expressways, neither of which terminate at the interchange, plus US 5. Straight out of the "only in Massachusetts" category. They finally striped it for 2 lanes during the last repaving project, so it isn't as much of a charlie foxtrot as it once was, but it is still bad. Good luck finding another quadruple trumpet.

I'd nominate Exit 13 on I-91 (US 5) as more unique than the I-91/MassPike/US 5 connection.

Looks like the figure eight in Poughkeepsie, NY.

[national highway 1]

This interchange at the junction of I-95 and I-280 in New Jersey.
https://www.google.com/maps/@40.7532612,-74.1173765,1081m/data=!3m1!1e3

[Henry]

Also from MA, the quadruple trumpet in West Springfield. 2 major expressways, neither of which terminate at the interchange, plus US 5. Straight out of the "only in Massachusetts" category. They finally striped it for 2 lanes during the last repaving project, so it isn't as much of a charlie foxtrot as it once was, but it is still bad. Good luck finding another quadruple trumpet.

Years ago I pointed out that interchange as special or confusing on m.t.r. and a couple of people actually responded that it's "just" a trumpet interchange.  *sigh*

Wow, that's a lot of trumpets! 

Guess we'll have to start calling that the John Williams Interchange.

I GET IT. 10/10

We have a winner!

[jeffandnicole]

I've always found the interchange between I-476 and PA 3 in Broomall, PA to be a tad bit peculiar (though it doesn't nearly compare to the other ones posted in the thread). It's a perfect diamond interchange with one cloverleaf ramp for PA 3 west to I-476 south. Traffic can't turn left at the traffic signal beyond the cloverleaf ramp (nor can they turn right from the opposite direction), yet there's marked and usable pavement for motorists to use if they choose to make the illegal left or right. This small ramp connecting PA 3 to the ramp from 3 east to 476 south is only legally allowed to be used by traffic coming off of I-476 south on the offramp, which even has it's own designated lane as you approach the intersection. Forgive me if there are a bunch of other examples of this same situation, but I thought it was interesting.

This setup is used, almost always, for two reasons:

1) Transit stops on the ramps, thus permitting re-entry for buses
2) re-entry for overheight vehicles unable to use the freeway underpass

EDIT: Your example is definitely for reason 2.

No it's not.  I-476 has no clearance issues whatsoever.

[roadman65]

The way US 70 intersects I-95 since they built the freeway for it between Goldsboro and I-40 just outside the Metro Raliegh area.
https://www.google.com/maps/@35.5086162,-78.2815112,3a,75y,17.54h,86.21t/data=!3m6!1e1!3m4!1sxG4-vkK4s1AmuUj0y1UKzQ!2e0!7i13312!8i6656!6m1!1e1

Here you see how its signed.  Mainline US 70 exits itself here to use the city streets of Selma to interchange with I-95 and junction with US 301.  Meanwhile the freeway is Bypass US 70 until its parent reenters the freeway a few miles later.

I do not think there is something ever like this anyplace although US 63 and I-70 have the same type of set up.  However, US 63 does not leave the freeway to do a Breezewood like US 70 does here.  US 63 is on the freeway and the surface connection roadway is just not signed as any part of US 63.

[paulthemapguy]

I've always found the interchange between I-476 and PA 3 in Broomall, PA to be a tad bit peculiar (though it doesn't nearly compare to the other ones posted in the thread). It's a perfect diamond interchange with one cloverleaf ramp for PA 3 west to I-476 south. Traffic can't turn left at the traffic signal beyond the cloverleaf ramp (nor can they turn right from the opposite direction), yet there's marked and usable pavement for motorists to use if they choose to make the illegal left or right. This small ramp connecting PA 3 to the ramp from 3 east to 476 south is only legally allowed to be used by traffic coming off of I-476 south on the offramp, which even has it's own designated lane as you approach the intersection. Forgive me if there are a bunch of other examples of this same situation, but I thought it was interesting.

This setup is used, almost always, for two reasons:

1) Transit stops on the ramps, thus permitting re-entry for buses
2) re-entry for overheight vehicles unable to use the freeway underpass

EDIT: Your example is definitely for reason 2.

No it's not.  I-476 has no clearance issues whatsoever.

Emphasis on "overheight," i.e. vehicles that exceed regulations for height.  You never know what kind of crazy monstrosities a trucking company might need to haul, like a big bulldozer, a steel beam, or a big piece of precast concrete.  These situations are anomalies but they do happen; when they do, clearance issues are inevitable no matter what standard the bridges/underpasses adhere to.  Similarly, an overWEIGHT truck will need to avoid certain bridges OVER things, even though the bridge is built to a respected standard, just because the weight of the object being hauled is just colossal.  I'm sure all this stuff is intuitive enough, and it's nothing new; what I want to emphasize here is that you can have all sorts of crazy colossal vehicle dimensions and weights that are difficult to accommodate regardless of bridge/highway standards.

[kurumi]

The way US 70 intersects I-95 since they built the freeway for it between Goldsboro and I-40 just outside the Metro Raliegh area.
https://www.google.com/maps/@35.5086162,-78.2815112,3a,75y,17.54h,86.21t/data=!3m6!1e1!3m4!1sxG4-vkK4s1AmuUj0y1UKzQ!2e0!7i13312!8i6656!6m1!1e1

Here you see how its signed.  Mainline US 70 exits itself here to use the city streets of Selma to interchange with I-95 and junction with US 301.  Meanwhile the freeway is Bypass US 70 until its parent reenters the freeway a few miles later.

I do not think there is something ever like this anyplace although US 63 and I-70 have the same type of set up.  However, US 63 does not leave the freeway to do a Breezewood like US 70 does here.  US 63 is on the freeway and the surface connection roadway is just not signed as any part of US 63.

Slight derail, but in the area there are US 70, US 70A, US 70 Business, and US 70 Bypass, all signed. First time I've seen that many in one place. (Nashville metro has 31, 31A, 31E, and 31W, but not that close together.)

[jeffandnicole]

I've always found the interchange between I-476 and PA 3 in Broomall, PA to be a tad bit peculiar (though it doesn't nearly compare to the other ones posted in the thread). It's a perfect diamond interchange with one cloverleaf ramp for PA 3 west to I-476 south. Traffic can't turn left at the traffic signal beyond the cloverleaf ramp (nor can they turn right from the opposite direction), yet there's marked and usable pavement for motorists to use if they choose to make the illegal left or right. This small ramp connecting PA 3 to the ramp from 3 east to 476 south is only legally allowed to be used by traffic coming off of I-476 south on the offramp, which even has it's own designated lane as you approach the intersection. Forgive me if there are a bunch of other examples of this same situation, but I thought it was interesting.

This setup is used, almost always, for two reasons:

1) Transit stops on the ramps, thus permitting re-entry for buses
2) re-entry for overheight vehicles unable to use the freeway underpass

EDIT: Your example is definitely for reason 2.

No it's not.  I-476 has no clearance issues whatsoever.

Emphasis on "overheight," i.e. vehicles that exceed regulations for height.  You never know what kind of crazy monstrosities a trucking company might need to haul, like a big bulldozer, a steel beam, or a big piece of precast concrete.  These situations are anomalies but they do happen; when they do, clearance issues are inevitable no matter what standard the bridges/underpasses adhere to.  Similarly, an overWEIGHT truck will need to avoid certain bridges OVER things, even though the bridge is built to a respected standard, just because the weight of the object being hauled is just colossal.  I'm sure all this stuff is intuitive enough, and it's nothing new; what I want to emphasize here is that you can have all sorts of crazy colossal vehicle dimensions and weights that are difficult to accommodate regardless of bridge/highway standards.

Yeah, but in the Philly area in general, the infrastructure is so old and there are so many low-height and overweight situations on the local roadways and older highways that simply getting to that overpass wouldn't be possible from local roads.  Besides, there's no height signage, and overpasses before and after this overpass are about the same height.  Usually in over height situations, there are signs prior to the bridge cautioning truckers about the low height.

In this area, it's pretty much taken for granted that you must have your payload at 13' 6" or less.  14' may be the absolute maximum.  It's nearly impossible to get around otherwise.

The Blue Route was originally constructed from the I-76/PA Turnpike area down to this interchange at Rt. 3.  South of here was the subject of numerous lawsuits, and when it was finally built, it was only 4 lanes wide, not 6 lanes as the area north of it.  If I were to guess, these straight ramps are some kind of anomaly that remained after PennDOT fully completed the interchange.

[roadman65]

The way US 70 intersects I-95 since they built the freeway for it between Goldsboro and I-40 just outside the Metro Raliegh area.
https://www.google.com/maps/@35.5086162,-78.2815112,3a,75y,17.54h,86.21t/data=!3m6!1e1!3m4!1sxG4-vkK4s1AmuUj0y1UKzQ!2e0!7i13312!8i6656!6m1!1e1

Here you see how its signed.  Mainline US 70 exits itself here to use the city streets of Selma to interchange with I-95 and junction with US 301.  Meanwhile the freeway is Bypass US 70 until its parent reenters the freeway a few miles later.

I do not think there is something ever like this anyplace although US 63 and I-70 have the same type of set up.  However, US 63 does not leave the freeway to do a Breezewood like US 70 does here.  US 63 is on the freeway and the surface connection roadway is just not signed as any part of US 63.

Slight derail, but in the area there are US 70, US 70A, US 70 Business, and US 70 Bypass, all signed. First time I've seen that many in one place. (Nashville metro has 31, 31A, 31E, and 31W, but not that close together.)

You said it that only Nashville comes close.  No other situation arises like this one.  NCDOT did it to avoid a situation like two cities in Michigan did with US 127 (former US 27) where there are two simultaneous business routes on each side of the mainline.  So, according to wiki,  they opted for the bypass designation instead.

[formulanone]

FL 84 at I-95: has this ever been copied before?



Eastbound SR 84 traffic is elevated so that turning traffic to and from I-95 isn't quite impeded, and so thru SR 84 traffic doesn't have to stop.

There's also C/D lanes which lead to and from I-595.

[roadman65]

FL 84 at I-95: has this ever been copied before?



Eastbound SR 84 traffic is elevated so that turning traffic to and from I-95 isn't quite impeded, and so thru SR 84 traffic doesn't have to stop.

There's also C/D lanes which lead to and from I-595.

Quite original here.  Maybe this should replace the DDIs that are being built and proposed.

[NE2]

There's a partial version of that at DC 295 and Benning Road.

[empirestate]

FL 84 at I-95: has this ever been copied before?



Eastbound SR 84 traffic is elevated so that turning traffic to and from I-95 isn't quite impeded, and so thru SR 84 traffic doesn't have to stop.

There's also C/D lanes which lead to and from I-595.

Quite original here.  Maybe this should replace the DDIs that are being built and proposed.

That's a good one; I don't think I've ever seen it elsewhere. It seems like a good way to eliminate left turns, but the scale of construction and thus the expense likely make it impractical in most places.


iPhone

[AMLNet49]

Exit 38 on I-95 in Connecticut to the Merritt Parkway (Exit 54 on Merritt) needs a connector that has exit numbers of its own

This is not one interchange though. The "connector" is the Milford Parkway. There is a regular directional interchange between the Milford (Exit 2) and I-95 (Exit 38). The interchange at the northern end of the Milford (Exits 3-4) is an unusual interchange given that there is another exit in between the exits for CT-15 north and south.

[CobaltYoshi27]

Exit 38 on I-95 in Connecticut to the Merritt Parkway (Exit 54 on Merritt) needs a connector that has exit numbers of its own

This is not one interchange though. The "connector" is the Milford Parkway. There is a regular directional interchange between the Milford (Exit 2) and I-95 (Exit 38). The interchange at the northern end of the Milford (Exits 3-4) is an unusual interchange given that there is another exit in between the exits for CT-15 north and south.

I have always considered it one interchange considering the exits post I-95 or the Merritt depending on where you are exiting.

[davewiecking]

In the Fairland area of Montgomery County, Maryland is the interchange of U.S. 29 (Columbia Pike) and Md. 200 (ICC toll road).
It features: 
[...]

• A cloverleaf ramp to carry eastbound Md. 200 traffic to Briggs Chaney Road (it has a separate exit number);
• A jughandle ramp to carry southbound U.S. 29 traffic to Fairland Road;  and

[...]

Indeed an interesting one, and it's clearly all the same Interchange, despite the fact that ramps have different exit numbers. Because the rest of Exit 17 is a half diamond just east (no toll gantry between the two, and it's impossible to legally use just the part in the middle), should this whole thing be considered one interchange?

For some reason I've always been fascinated by the interchange of I 95, 295, 495 south of Wilmington. I'd say DE 141 is a separate interchange, but is the rest of this just one interchange? Ditto with the Shirlington interchange at the bottom of the DC beltway-even if you ignore the connected interchange with VA644 just south. Quite the convoluted collection of ramps connecting 2 highways, and their HOV lanes.

[Jardine]

FL 84 at I-95: has this ever been copied before?



Eastbound SR 84 traffic is elevated so that turning traffic to and from I-95 isn't quite impeded, and so thru SR 84 traffic doesn't have to stop.

There's also C/D lanes which lead to and from I-595.

I-80 and 24th street in Omaha is a pale shadow of that.

[Jardine]

This is spectacular: