3di/3dus

[Alps]

Many of us know that I-271/I-480 in Cleveland is the only place where two three-digit Interstates run concurrent.  What about 3-digit Interstate and 3-digit US highway?  We've generated two so far:

I-277/US 224 Akron
I-295/US 130 southern NJ

How many others are there?

[rawmustard]

Many of us know that I-271/I-480 in Cleveland is the only place where two three-digit Interstates run concurrent.  What about 3-digit Interstate and 3-digit US highway?  We've generated two so far:

I-277/US 224 Akron
I-295/US 130 southern NJ

How many others are there?

I-296/US 131 Grand Rapids
I-595/US 301 btw Bowie and Annapolis
I-465/US 421 Indianapolis

That's what I got off the top of my head.

Oooh, just confirmed it in the Rand McNally that there's I-530/US 167 south of Little Rock, but you didn't say we couldn't cheat.

[US71]

Many of us know that I-271/I-480 in Cleveland is the only place where two three-digit Interstates run concurrent.  What about 3-digit Interstate and 3-digit US highway?  We've generated two so far:

I-277/US 224 Akron
I-295/US 130 southern NJ

How many others are there?

I-244/US 412 Tulsa

[rickmastfan67]

Many of us know that I-271/I-480 in Cleveland is the only place where two three-digit Interstates run concurrent.

We have Future I-840 and I-785 in NC.

And for awhile here in Pittsburgh, I-279 and I-376 were co-signed together during the transition on the Parkway West from I-279 to I-376.

[Alps]

Many of us know that I-271/I-480 in Cleveland is the only place where two three-digit Interstates run concurrent.  What about 3-digit Interstate and 3-digit US highway?  We've generated two so far:

I-277/US 224 Akron
I-295/US 130 southern NJ

How many others are there?

I-296/US 131 Grand Rapids
I-595/US 301 btw Bowie and Annapolis
I-465/US 421 Indianapolis

That's what I got off the top of my head.

All of those are unsigned...

[rickmastfan67]

Here's one that is signed.

I-180 and US-220 here in PA.

[golden eagle]

I-380 and U.S. 218 in the Cedar Rapids area.

[corco]

I-182/US-395 in the Tri Cities, Washington, which is signed

[Ian]

I-393/US 202/US 4 in Concord, NH.

[mightyace]

and a brand new one...
I-376 and US 422 around New Castle, PA

US 422 also multiplexes with I-271 east of Cleveland, OH

[TheStranger]

IIRC, US 127 and I-496 run together for a brief segment in eastern Lansing.

[xonhulu]

Another future one: I-580/US 395 between Reno and Carson City

[KEK Inc.]

3dus is sort of rare in the West.  (Obviosly, US-101 doesn't count, and it's never concurrent with a 3di.)
197, 199, (299), (399), 395

All I can think of right now is Future I-580 and US-395 between Carson City and Reno and I-182/US-395, which was already posted. 

Edit:  Dammit.  And someone just posted the I-580/US-395 deal too. 

[rickmastfan67]

Here's an historical one.

I-485 and US-521 in Charlotte, NC.  That one existed till they shortened US-521 to start/end at I-485 just above the SC/NC State Border.

[rawmustard]

I-296/US 131 Grand Rapids
I-595/US 301 btw Bowie and Annapolis
I-465/US 421 Indianapolis

That's what I got off the top of my head.

All of those are unsigned...

And yet still concurrent!

Another future one: I-580/US 395 between Reno and Carson City

All the documentation I've read points to I-580 existing right now. Just because there are no I-580 shields does not mean it isn't a current route.

IIRC, US 127 and I-496 run together for a brief segment in eastern Lansing.

Dang, I knew I had brainfarted on one in my own state.

[TheStranger]

Forgot to mention I-410 and US 281 on the south side of San Antonio, between Roosevelt Avenue and I-37.

[rickmastfan67]

Here's another one that I just remembered.

I-585 and US-176 in Spartanburg, SC.

[mightyace]

Another one I remembered,

I-295 and US 130 in New Jersey.

[rickmastfan67]

Another one I remembered,

I-295 and US 130 in New Jersey.

That one was mentioned in the first post.

[deathtopumpkins]

Not sure if it counts or not but US 460 ALT is multiplexed with I-264 through the downtown tunnel and across the Berkeley Bridge between Portsmouth and Norfolk, VA, but is not signed on the interstate

EDIT: Oh and a defunct one: I-795 and US 117 in North Carolina. IIRC 117 was recently moved back to it's original alignment.

[TheStranger]

The entirety of North Carolina's new I-795 is corouted with 3dus routes!  (US 117 for a majority of it, US 264 at the north end)

EDIT: As noted by deathtopumpkins' post above, 117 is now on old US 117A, but that leaves US 264 with I-795 at the north terminus!  Not sure if 117 runs with the 795/264 concurrency now.

[deathtopumpkins]

Interesting timing. You beat me by about a minute.

[TheStranger]

Another Texas example came to mind just now: I-820 and US 287 between I-20 and I-820 Exit 33A, in southeast Fort Worth.

Isn't all of I-155 in Tennessee corouted with US 412?

I-581 and US 220 are concurrent for I-581's entirety.

US 129 also has a brief concurrency with I-985 in Georgia...

[US71]

I-530/US 167

[hbelkins]

Someone beat me to I-581 and US 220.

How about former I-181 and US 19W in Tennessee? No one said one of the digits in the 3dus couldn't be a letter.