Interstates (or other limited access roadways) that are virtually just ramps

[kkt]

Title. A limited access roadway that, on its entire length, has no on or off ramps. (Except where it begins and ends, how else are you going to get on one? (with the exception of intersections)) I know of two Interstates like this, I-189 in VT and I-781 in NY.

I-238 (duck) in Alameda County, California is basically just a long connector ramp. The entire CASR-238 (including the part that isn't Interstate or even limited access) extends quite a bit further.

No, I-238 in Alameda County does have entrances and exits besides at its ends.

Hesperian Blvd to eastbound I-238
westbound I-238 to Springlake Dr.
eastbound I-238 RORO to Lewelling Blvd
westbound I-238 RORO to 170th Ave.
eastbound I-238 to Mattox Rd./CA 238
CA 238/Mattox Rd. to westbound I-238

[ilpt4u]

The Ends Spur (I-94) between the Edens Expressway/Skokie Highway and the Tri-State Tollway, north of Chicago, comes pretty close to a long set of ramps from the Edens to the Tri-State, but it has one intermediate half-interchange, with Westbound On/Eastbound Off @ Waukegan Rd/IL-43

[vdeane]

Autoroute 930, if you count A-30 and Boul Jean-Leman as one interchange.

Title. A limited access roadway that, on its entire length, has no on or off ramps. (Except where it begins and ends, how else are you going to get on one? (with the exception of intersections)) I know of two Interstates like this, I-189 in VT and I-781 in NY.

Sorry if there's a thread for this, I looked at over ten pages in search results and found no thread similar to this.

I-781 ends at Fort Drum, not US 11, so it does not count.

I-587
I-695 (NY)
I-478 (unsigned, though it is an important connection between boros)
I-495 (ME, unsigned)
I-283

I-695 has intermediate ramps.  I-283 too, though it was already mentioned.

[RobbieL2415]

NY 912M.

[Mergingtraffic]

I-395, I-895A, I-895B in Baltimore.  (Technically the one 895 Spur has a ramp to another spur, but I consider both a ramp off mainline 895)

Nexus 6P

I-395 has one exit, to MLK Jr Blvd.

[roadman65]

The Crosstown Connector in Tampa.  Although one may argue that the Port of Tampa Truck access counts as an exit its actually a separate carriageway running parallel to the two main freeway alignments which has one going from EB I-4 to EB FL 618 and WB 618 to WB I-4, as well as from WB I-4 to WB FL 618 and EB FL 618 to I-4 EB.

[NE2]

The Crosstown Connector in Tampa.  Although one may argue that the Port of Tampa Truck access counts as an exit its actually a separate carriageway running parallel to the two main freeway alignments which has one going from EB I-4 to EB FL 618 and WB 618 to WB I-4, as well as from WB I-4 to WB FL 618 and EB FL 618 to I-4 EB.

That's not virtually ramps. It is ramps.

[MASTERNC]

I-579 in Pittsburgh

[hotdogPi]

I-579 in Pittsburgh

Nope. There are intermediate ramps.

[Mr_Northside]

I-579 in Pittsburgh

Nope. There are intermediate ramps.

And a fairly significant bridge crossing the Allegheny.

[bzakharin]

The PA extension of the NJ turnpike if you consider the toll plaza as its western terminus. Of course it's either not an interstate or part of I-95, so it's technically ineligible.

[cpzilliacus]

The PA extension of the NJ turnpike if you consider the toll plaza as its western terminus. Of course it's either not an interstate or part of I-95, so it's technically ineligible.

The New Jersey  Turnpike continues to the state line at about the peak of the Delaware River—Turnpike Toll Bridge. Traffic entering from U.S. 130 to head toward Pennsylvania must pay a New Jersey Turnpike toll, in addition to the cashless toll point entering Pennsylvania.

It is officially part of I-95, but will not be signed until PTC (and PennDOT) finish enough of the interchange at Bristol, Pennsylvania (link to thread here on AARoads) to complete I-95.

Beyond any of the above, the  interchange at U.S. 130 (the only interchange on the New Jersey  Turnpike without a number, I  believe) would presumably make it ineligible anyway.

[bzakharin]

The PA extension of the NJ turnpike if you consider the toll plaza as its western terminus. Of course it's either not an interstate or part of I-95, so it's technically ineligible.

The New Jersey  Turnpike continues to the state line at about the peak of the Delaware River—Turnpike Toll Bridge. Traffic entering from U.S. 130 to head toward Pennsylvania must pay a New Jersey Turnpike toll, in addition to the cashless toll point entering Pennsylvania.

You are right. I didn't realize there was a toll there as I've never taken that interchange. I've done the reverse, though, and there is no toll at the exit coming from PA, so maybe only the Eastbound extension sort of meets the criteria.

It is officially part of I-95, but will not be signed until PTC (and PennDOT) finish enough of the interchange at Bristol, Pennsylvania (link to thread here on AARoads) to complete I-95.

You don't have to tell me. I've briefly acknowledged such in my original post. However, it's currently unsigned, and historically had its own (also unsigned) non-Interstate designation.

Beyond any of the above, the  interchange at U.S. 130 (the only interchange on the New Jersey  Turnpike without a number, I  believe) would presumably make it ineligible anyway.

The 130 exit is officially 6A, though it's not signed. There is an unnumbered exit south of the "Exit 1" toll plaza to US 40 / NJ 140 / CR 540. Like 6A (at least Eastbound), it's outside the tolled area.

[bing101]

The old Embarcadero Freeway originally signed as I-480 and later CA-480 was viewed as a ramp for Downtown and was intended to connect CA-480 to golden gate bridge.

[US 89]

The old Embarcadero Freeway originally signed as I-480 and later CA-480 was viewed as a ramp for Downtown and was intended to connect CA-480 to golden gate bridge.

But there were several exits and entrances on that freeway.