Really long interchanges

[Road Hog]

High 5 Interchange in Dallas is the best example I can think of around here. The longest ramp is from I-635 westbound to US 75 southbound, which is about 1.9 miles.

This was exactly the interchange I was thinking of. From off-ramp to on-ramp in each direction is probably 3 miles all told.

[triplemultiplex]

This puffed up trumpet at the junction of I-39/US 51 and US 10 west is in the spirit of this thread:

http://mapper.acme.com/?ll=44.59520,-89.61629&z=15&t=S

It's much bigger than one would've expected and seems to have only been done that way to avoid moving a mere county road.

[NE2]

It's much bigger than one would've expected and seems to have only been done that way to avoid moving a mere county road.

Because nobody cares how fast they can go on the ramp...

[JustDrive]

NB 215/WB 60 to WB 91 in Riverside.  It's about 1.3 miles long.  Same with SB 215 to EB 60/SB 215.

[kphoger]

If you never change lanes after exiting, cloverleaf interchanges are infinitely long.

[jp the roadgeek]

Most of the left hand exits off of I-84 between Waterbury and East Hartford, CT are really long because they are the stub end of unbuilt freeways.  Exit 29 (WB Only), 39, 43, 45 (WB only), 46, 48A (EB only), and 56 all fall into this category.  Another glorified long exit ramp is the CT 32 connector (Exit 78) off of I-395.  While it does have its own state route designation (SSR 693), it has no exits between I-395 and CT 32.

[lepidopteran]

The interchange between I-71 and the western terminus of the eastern I-76.  It used to be an annoying double trumpet, typical of an interchange where one or both highways are toll roads, but neither is a toll road.  A look at Google Maps says that the connections are now more direct, though some of the ramps still seem kind of long.

The I-275/I-75 junction near Monroe, MI seems rather lengthy for a T-interchange.

On the New Jersey Turnpike, as part of the Exit 6-to-9 widening project, they are building an "interchange" leading to one of the service plazas near Exit 7; they need flyover ramps to get the inner roadway to and from the plaza.  But at least one of the under-construction flyovers seems quite far away from the plaza itself.

[nwi_navigator_1181]

The ramp separating I-94 west from I-80 west in Illinois is a good example. The gore point starts less than a mile after crossing into the state, follows alongside I-80, then pulls away and finally merges with traffic on Illinois 394...nearly three miles after the initial separation. (This does not take into account the separation for Illinois 394 southbound traffic.)

Another candidate could be the high ramps connecting the Tri-State Tollway (I-294) to the westbound Jane Addams Tollway (I-294 North to I-90 West) or Kennedy Expressway (I-294 South to I-90 East). They go for about 1.5 miles before the transition is completed.

[Bickendan]

I-84/US30 and I-205 in Portland/Maywood Park. It's so long (Exits 6-9 on I-84/US30, 20-21 on I-205), it hits two cities!
link

[oscar]

The sprawling Halawa Interchange west of Honolulu includes a mile-long ramp from Interstate H-1 eastbound to Interstate H-201 eastbound.  That ramp also connects to Interstate H-3 eastbound.  There are also ramps to HI 78, HI 99, and HI 7241 elsewhere within the interchange.

[realjd]

I forgot the one in Celebration, FL where I-4 and the southern terminus of FL 417 meet.  Despite the c/d road that is there, the point of diversion from the c/d road and FL 417 to the point where FL 417 departs I-4 is long itself.  In addition to the 1 mile of c/d road you have another 3/10 of a mile to go for something as simple as a typical directional set up.

Several of the interchanges along that stretch of I4 (US192, SR536, Osceola Pkwy) are longer than usual due to the way they weaved the ramps together. Same goes for where Kirkman, Universal, and Sand Lake all meet I4.

Another interesting one from near where I used to live is the I69/I469 interchange on the north side of Fort Wayne, IN. There's a mile-ish spur ramp going away from the interstates, snaking between some buildings, exiting onto a local road.

[vdeane]

ON 400 at ON 407.  The 407 ramps actually pass two other interchanges (one on either side).

[PHLBOS]

Most of the left hand exits off of I-84 between Waterbury and East Hartford, CT are really long because they are the stub end of unbuilt freeways.  Exit 29 (WB Only), 39, 43, 45 (WB only), 46, 48A (EB only), and 56 all fall into this category.  Another glorified long exit ramp is the CT 32 connector (Exit 78) off of I-395.  While it does have its own state route designation (SSR 693), it has no exits between I-395 and CT 32.

Don't forget Exit 27, the I-84/691 interchange.

[thenetwork]

The I-275/I-75 junction near Monroe, MI seems rather lengthy for a T-interchange.

Not to mention, for the I-275 South traveler, you can easily get tripped up since at the I-75 split, the SOUTHBOUND ramp is on the left, while the NORTHBOUND ramp is on the right.  It happened to my parents two times, despite the signage, as it it is somewhat a natural reflex that you want to be in the right lanes to go right.

[NE2]

It's also a natural reflex to go straight to go straight. I-275 follows this, as both lanes follow the main through movement, while the sharp left turn is an exit off to the right.

[mgk920]

This puffed up trumpet at the junction of I-39/US 51 and US 10 west is in the spirit of this thread:

http://mapper.acme.com/?ll=44.59520,-89.61629&z=15&t=S

It's much bigger than one would've expected and seems to have only been done that way to avoid moving a mere county road.

I've always thought that that one was designed that way to allow full speed on the US 10 ramps in an area with relatively cheap land.

The ramp separating I-94 west from I-80 west in Illinois is a good example. The gore point starts less than a mile after crossing into the state, follows alongside I-80, then pulls away and finally merges with traffic on Illinois 394...nearly three miles after the initial separation. (This does not take into account the separation for Illinois 394 southbound traffic.)

Another candidate could be the high ramps connecting the Tri-State Tollway (I-294) to the westbound Jane Addams Tollway (I-294 North to I-90 West) or Kennedy Expressway (I-294 South to I-90 East). They go for about 1.5 miles before the transition is completed.

Don't forget I-88/355 in west suburban Chicagoland.



Also, the NB off ramp for 75th St (interchange 227) in the SW Kansas Kansas City suburbs diverges from I-35 a short distance south of 87th St (interchange 225).

Mike

[lordsutch]

It's also a natural reflex to go straight to go straight. I-275 follows this, as both lanes follow the main through movement, while the sharp left turn is an exit off to the right.

The one that throws me is where the ramp to logically go left is before the one to go right; this pattern is somewhat common in Texas where they added flyovers later to fix an underpowered loop ramp but didn't move the original 90-degree ramp at the same time; I-635 at I-30 is a good example, but there are others.  The interim state of the I-40/240 east interchange in Memphis (allegedly to finally restart construction this year) is the same way, although less egregious since–except the way locals think–the north loop isn't part of I-240 anymore.

[leroys73]

Garden Ridge &  I-35E in Highland Village north of Dallas.  It is a bit complex. 

[empirestate]

Garden Ridge &  I-35E in Highland Village north of Dallas.  It is a bit complex. 

It does look a little weird; I don't know if I'd go as far as "complex" (but of course, where I live there are tons of funny-looking interchanges like that). I see that the SB exit ramp is way to the north, which does make the interchange pretty long, and which probably happens a lot given the typical frontage road setup in Texas.

A side question could be, in a Texas frontage road system, what's the farthest in advance an exit ramp diverges, in relation to its signed destination?

[ftballfan]

The main example that came to mind for me was the junction of I-96 and I-69 on the northwest side of the Lansing MI area. Going eastbound on I-96, it's Exit 89 for eastbound I-69. Going westbound on I-96 (concurrent with northbound I-69), the exit to head east on I-69 is Exit 91. There are several occasions throughout the year when I take the east-96-to-east-69 movement. That is quite a long ramp - as is the ramp from westbound I-69 to westbound I-96. Those ramps are probably at least two miles long.

It's so long that Exit 90 is squeezed in between the two ramps along I-96.

[InterstateNG]

A side question could be, in a Texas frontage road system, what's the farthest in advance an exit ramp diverges, in relation to its signed destination?

Some examples from around Austin:

EB 290 -> SB Mopac:  1.4 mi
EB 290 -> Brodie Lane:  1.3 mi

WB 290 -> NB Mopac:  1.5 mi

NB 35 -> WB 2222:  .9 mi

NB 35 -> EB 183:  1.9 mi

WB183 -> NB 35:  1.9 mi

EB 183 -> NB 35:  2 mi

I used from where you get off one freeway to where you get on the other for these measurements.

[vdeane]

The main example that came to mind for me was the junction of I-96 and I-69 on the northwest side of the Lansing MI area. Going eastbound on I-96, it's Exit 89 for eastbound I-69. Going westbound on I-96 (concurrent with northbound I-69), the exit to head east on I-69 is Exit 91. There are several occasions throughout the year when I take the east-96-to-east-69 movement. That is quite a long ramp - as is the ramp from westbound I-69 to westbound I-96. Those ramps are probably at least two miles long.

It's so long that Exit 90 is squeezed in between the two ramps along I-96.

Same thing happens in the interchange between the Mon-Fayette Expressway and US 119 in PA.

[Revive 755]

There's a fairly large modified diamond interchange where US 67 crosses MO 34:
http://maps.google.com/maps?q=Fredericktown,+MO&hl=en&ll=37.185006,-90.461726&spn=0.029096,0.066047&sll=37.184288,-90.47164&sspn=0.029096,0.066047&oq=fred&t=m&hnear=Fredericktown,+Madison,+Missouri&z=15

[sandiaman]

I-10 eastbound  in El Paso  has  a very  long  ramp  going  to  US 54,  ( JUAREZ, ALAMOGORDO).   When  it  was  built  in  the  late 70's, it was  reputed  to be  the  longest  in  the  state  of  Texas.

[lepidopteran]

There was a unique example of a "long" off ramp on I-70 in Eastern Ohio, though I'm not completely sure of the location.  To get off at a certain exit going eastbound, you had to get off at a rest area (which a historic topo map identifies as a weigh station) but stay on a C/D road that continued on to the exit ramp.  I think this was the exit for Mall Rd./Benfield Rd. in St. Clairsville.  The rest area that closely precedes it appears to be abandoned, but the pavement is still present.  The connecting road, if this is in fact the location I'm thinking of, has been dug up.