Freeways that end at roundabouts

[cl94]

If we include super twos, then Waterloo Region has one. Hwy 85 goes from a four-lane divided highway to a super two, becoming RR 85. Then it meets a roundabout at RR 17 (with no intersections or interchanges along this segment).

Given that NY 85 and MA 28 are on the list, I'd say it's worth including.

[bzakharin]

I-587.

This one takes the cake.  Western end is a rotary, eastern end is a signalized intersection.  Is it the only 3DI not to directly end at its parent?

No. I-790 is another. Technically ends at Leland Avenue (NY 5). Getting to I-790 from I-90 requires going through a signalized intersection.

There are many interstates that don't *end* at the parent. Just in my area, I-287 ends at I-95 at both ends, but has a multiplex with I-87. I-195 interchanges with I-95 in the middle, but ends at I-295 at one end. I-495 is not connected to I-95 except via I-695.

There are also ones that never connect to their parent except by an unrelated Interstate. E.g. I-278, which only connects to I-78 via I-95

[froggie]

Some of these examples are traffic circles, not roundabouts.  Yes, there's a difference...

[jakeroot]

Some of these examples are traffic circles, not roundabouts.  Yes, there's a difference...

That's what I've been thinking. The OP needs to clarify whether or not traffic circles count -- I don't think they should.

[Buffaboy]

My favorite: NY-179 at NY-5.

Disclaimer: it's a rotary

[Duke87]

In my opinion, I don't think it's a good idea to have a roundabout at the end of a high speed roadway since people don't expect to see a roundabout on a road signed at 65 mph in a rural setting.

People won't expect a traffic signal, either. Or anything else that impedes them from continuing to travel straight ahead at freeway speeds. Which is why any such instance needs plenty of warning signage.

The US 53 example does not strike me as particularly heinous. It is at the point where the divided highway ends, and on top of that it is located directly past the interchange with I-94, which runs parallel to undivided US 53... thereby meaning that only local traffic is going to go through that roundabout.

[TheHighwayMan3561]

The east end of the US 2 freeway in Superior, WI was rebuilt into a roundabout last year. But the speed limit drops to 35 before you reach the roundabout.

[froggie]

The east end of the US 2 freeway in Superior, WI was rebuilt into a roundabout last year. But the speed limit drops to 35 before you reach the roundabout.

One could also argue that that isn't a freeway but instead a glorified bridged access ramp to/from I-35...

[machias]

I-587.

This one takes the cake.  Western end is a rotary, eastern end is a signalized intersection.  Is it the only 3DI not to directly end at its parent?

No. I-790 is another. Technically ends at Leland Avenue (NY 5). Getting to I-790 from I-90 requires going through a signalized intersection.

Actually, while I-790 doesn't connect to I-90, it actually ends at the Genesee Street overpass. The portion from the overpass to Leland Ave is considered a ramp.

[cl94]

I-587.

This one takes the cake.  Western end is a rotary, eastern end is a signalized intersection.  Is it the only 3DI not to directly end at its parent?

No. I-790 is another. Technically ends at Leland Avenue (NY 5). Getting to I-790 from I-90 requires going through a signalized intersection.

Actually, while I-790 doesn't connect to I-90, it actually ends at the Genesee Street overpass. The portion from the overpass to Leland Ave is considered a ramp.

That's even less logical.

[Rothman]

I-587.

This one takes the cake.  Western end is a rotary, eastern end is a signalized intersection.  Is it the only 3DI not to directly end at its parent?

No. I-790 is another. Technically ends at Leland Avenue (NY 5). Getting to I-790 from I-90 requires going through a signalized intersection.

Actually, while I-790 doesn't connect to I-90, it actually ends at the Genesee Street overpass. The portion from the overpass to Leland Ave is considered a ramp.

That's even less logical.

Yep.  Any attempt to clinch it makes anyone wonder why the designation exists at all.

[jp the roadgeek]

If we are counting traffic circles, then the Whitehead Highway's (formerly part of the proposed I-484) in Hartford, CT west end is Pulaski Circle (east end is I-91)

[cl94]

If we are counting traffic circles, then the Whitehead Highway's (formerly part of the proposed I-484) in Hartford, CT west end is Pulaski Circle (east end is I-91)

I think we should count them. Quite common on older freeways out east and, in many ways, even more unexpected due to the fast speeds of intersecting traffic.

[bzakharin]

The South end of the US 202/206 freeway section used to end in a traffic circle. Now that the US 202 flyover is built, though 206 still goes to the traffic circle, it is signed as an exit from 202, whose freeway portion now ends just beyond the traffic circle at a signal.

[Duke87]

No. I-790 is another. Technically ends at Leland Avenue (NY 5). Getting to I-790 from I-90 requires going through a signalized intersection.

Actually, while I-790 doesn't connect to I-90, it actually ends at the Genesee Street overpass. The portion from the overpass to Leland Ave is considered a ramp.

That's even less logical.

This is most likely a vestige of the fact that originally I-790 followed a 2-lane roadway to the south of the Thruway which fed directly into the Thruway ramps (the current direct ramp from 790 to the Thruway is a remnant of this). In such a configuration it made some sense for 790 to end at Genesee Street because beyond there would have been NYSTA maintained roadway which predated 790's construction.

When the current straddling carriageway setup was built, whoever was doing the bookkeeping probably just didn't see fit to change the listed endpoint of I-790.

[Chris]

The first generation of 'interchanges' between motorways in the Netherlands were roundabouts / traffic circles. Some had gas stations on it. The busiest interchange in the Netherlands was orginally built as a traffic circle in 1939.

The last motorway-to-motorway at-grade roundabout interchange in the Netherlands is currently being replaced with a new directional T interchange, near the town of Joure.



Many autovías in Spain start or end at roundabouts, in particular urban / metropolitan autovías that do not carry a whole lot of through traffic. Like in the UK, some motorway-to-motorway interchanges in Spain also include roundabouts. For example the A-62/A-66 interchange in Salamanca is a roundabout.

R9 in Charleroi, Belgium is a one-way motorway, it basically functions like a giant roundabout around downtown with up to four lanes.

[silverback1065]

I don't think this is very common, but US 53 is a freeway that ends at a roundabout in Eau Claire, WI.  US 10 in Marshfield is also a freeway/expressway that ends at a roundabout.  Changes were recently made to the US 53/Old Town Hall Rd roundabout which included adding rumble strips and installing a mound in the roundabout circle because there were a lot of crashes, I'm guessing because people don't expect to see a roundabout while driving down a freeway.  Before the roundabout, US 53 transitioned into a 2 lane rural roadway and the intersection was just a rural intersection.  A retail store was built in the area and developers wanted to develop the area, so a roundabout was built in anticipation of new development at the intersection.

In my opinion, I don't think it's a good idea to have a roundabout at the end of a high speed roadway since people don't expect to see a roundabout on a road signed at 65 mph in a rural setting. 





Here is an article on the recent improvements:
http://www.leadertelegram.com/News/Daily-Updates/2016/06/13/State-to-improve-U-S-53-roundabout.html

the freeway ends at i-94, besides if there is adequate signage, it doesn't matter.

[silverback1065]

I-587.

how is this allowed to be an interstate?

[empirestate]

I-587.

how is this allowed to be an interstate?

Why shouldn't it be?


iPhone

[cl94]

I-587.

how is this allowed to be an interstate?

Why shouldn't it be?


iPhone

Better question: Why is Wyoming I-180 an Interstate?

[silverback1065]

I-587.

how is this allowed to be an interstate?

Why shouldn't it be?


iPhone

Better question: Why is Wyoming I-180 an Interstate?

another good question that no one has given me a good answer to.

[jakeroot]

Better question: Why is Wyoming I-180 an Interstate?

another good question that no one has given me a good answer to.

Well, it was built using federal interstate dollars. A better question is: why did the expressway receive federal funding? Was I-180 originally envisioned as grade-separated, before being downgraded?

[jakeroot]

The last motorway-to-motorway at-grade roundabout interchange in the Netherlands is currently being replaced with a new directional T interchange, near the town of Joure.

I really like the way that the Netherlands has adopted spiral markings, even at the very largest of roundabouts. This marking method is what I'd like to see adopted in the US at large traffic circles, such as those in Massachusetts, that aren't already being changed to smaller roundabouts.

[mgk920]

The German A27 ends at a roundabout in Cuxhaven.

https://www.google.com/maps/@53.8393957,8.732678,1915m/data=!3m1!1e3

Mike

[empirestate]

I-587.

how is this allowed to be an interstate?

Why shouldn't it be?


iPhone

Better question: Why is Wyoming I-180 an Interstate?

another good question that no one has given me a good answer to.

But my question is why wouldn't they be? In I-180's case, that's obvious: Interstate aren't supposed to have intersections. But what's the reason with I-587? What characteristics does it have that Interstates aren't "supposed to" have?