Should one-state interstates be called interstates?

[mjb2002]

Almost every Interstate is connected to the main system (but not I-2 right now, or Alaska or Hawaii). So from almost every Interstate, you can get to another state using just the Interstate system.

Alaska and Hawaii should not have them, though.

I wonder, aside from your exceptions, is there any piece of interstate from which you can't get to all other pieces of interstate using just the interstate system? If not, what was the last such piece and when was it connected to the rest of the system? I'm guessing this happens sometimes during construction of new interstates.

I 73/74 in North Carolina was disconnected from the rest of the system from 1997 until 2013, when the US 220 freeway ( I 73/74 Future) from Asheville to Greensboro was upgraded and signed as Interstate.

Are you sure that US 220 is near Asheville? Or did you mean Asheboro?

[hbelkins]

I believe I-99 officially ends at the interchange between I-99/US 220 and Alt US 220 to the PA Turnpike.

I thought I had a photo of mile marker 0 on I-99 but I'm having no luck finding it so far.

[zzomtceo]

Almost every Interstate is connected to the main system (but not I-2 right now, or Alaska or Hawaii). So from almost every Interstate, you can get to another state using just the Interstate system.

Alaska and Hawaii should not have them, though.

Doesn't I-2 connect with I-69 C and E? Although I-69C and I-69E in that area don't connect as freeway to other parts of the system, they do as a highway though.

[zzomtceo]

Interstates are all freeways but not all freeways are interstates.

Except of course I-180 in Wyoming.

I-69 In southern Texas by I-2.

[Jim]

Some people believe I-587 does not connect to the I- system. I happen to count the circle as part of the NY Thruway interchange.

I also consider I-587 connected by the interchange, but it would feel much more legitimate if its parent acknowledged its existence.