Interstates on Islands

[dbz77]

Which interstates traverse islands? I know that H-1, H-2, and H-3 are in  Oahu, I-95 crosses the northern part of Manhattan island in New York, and part of I-710 is in Terminal island in California.

[oscar]

Also H-201. And unsigned PRI-1, -2, and -3 in Puerto Rico.

Part of I-190 in New York traverses Grand Island, NW of Buffalo.

Part of I-90 in Washington state traverses Mercer Island near Seattle.

I-195 in Florida ends in Miami Beach, which is at least technically mostly on an island (more technically than Grand and Mercer islands, with only narrow waterways cutting it off from the mainland).

There are undoubtedly others.

[GaryV]

A bit of I-75 in Sault Ste Marie is on an island formed by the hydro power canal.

[Molandfreak]

I-90 also has an exit on French Island west of La Crosse, WI.

[froggie]

Staten Island, NY

Long Island, NY (which from a geography perspective also includes Brooklyn and Queens)

Because of the Tidal Basin and Washington Channel, Potomac Park (DC) is technically an island so I-395.

I-10 across Mobile Bay (AL)

I-5 on Hayden Island in Portland, OR

[Rothman]

I-81, Wellesley Island.

[US 89]

I-80, Yerba Buena Island, CA
I-90, Mercer Island, WA
I-66, Theodore Roosevelt Island, DC

And yes, anything on Manhattan or Long Island or Staten Island. That's I-95, I-78, I-295, I-495, I-278, I-678, and unsigned I-478 and I-878.

[CtrlAltDel]

I don't know if this counts, since there's a causeway, but I-24 in TN near Chattanooga:

[webny99]

Since a lot of the obvious ones have been mentioned - not sure how granular we want to get but there are plenty of uninhabited island crossings, such as I-76 and I-81 where they cross the Susquehanna near Harrisburg.

[RobbieL2415]

I-190 over Grand Island, NY

[Ga293]

Interstate 95 crosses several in Georgia, two of which are permanently inhabited.

[SP Cook]

Not one very many would guess, but I-70 uses Wheeling Island to cross the Ohio, and has an exit, one of the few Exit 0 in the system, on it.  Well, half an exit.

[CoreySamson]

The only Texas examples I know of:

- I-45 ends on Galveston Island
- I-10 technically travels over an island while crossing Old River Lake near Cove

[Mapmikey]

I-526 Daniel Island

[Crown Victoria]

I-79 Neville Island

I-76 Fourteen Mile Island (Allegheny River)

I-80 crosses over an island while crossing the Delaware River between PA and NJ.

[jp the roadgeek]

I-278 on Randall's Island.

I-95 in Manhattan (as well as the western tip of I-495, silent I-478 at the north end of the Battery Park Tunnel, and I-78 at the east end of the Holland Tunnel)

[MATraveler128]

I-275 in Florida traverses some islands as it crosses Tampa Bay.

[SkyPesos]

I-270 Choteau Island (between Mississippi River and Chain of Rocks Canal)

[bing101]

https://en.wikipedia.org/wiki/List_of_highways_in_Puerto_Rico

There are interstates in Puerto Rico with the I-PR1, I-PR2 and I-PR3 on the Island

[GenExpwy]

The man-made islands on the bridge/tunnel crossings on I-64 and I-664, Hampton Roads VA.

[mgk920]

A bit of I-75 in Sault Ste Marie is on an island formed by the hydro power canal.

I-75 ends where the concrete median wall ends just south of the bridge tollgate.  It does not reach any of the water.

Mike

[ilpt4u]

Would I-10 on the east side of New Orleans count? It appears water-locked on the map.

Never been to NOLA so no first hand experience

[CtrlAltDel]

A bit of I-75 in Sault Ste Marie is on an island formed by the hydro power canal.

I-75 ends where the concrete median wall ends just south of the bridge tollgate.  It does not reach any of the water.

The Wikipedia article has this to say:

The sign assembly erected by MDOT indicates that I-75 ends just south of the toll and customs plaza for the International Bridge,[25] however according to MDOT's Physical Reference Finder Application online[2] and the Federal Highway Administration's Route Log and Finder List,[26] I-75 continues onto the International Bridge and ends at the international border in the middle of the St. Marys River.

[andrepoiy]

All of Montreal and Laval for Quebec.

[Bruce]

I-5 crosses three islands in the Snohomish River Delta between Everett and Marysville.

I-5 also crosses Hayden Island in northern Portland, while I-205 crosses Government Island.