"Century" Multiplexes - Interstate and US Routes that add up to 100

[Henry]

Since Interstate numbers and US numbers are sequenced in opposite directions (from north to south and east to west), it's probably not too uncommon to see multiplexes that add up anywhere you look close to 100, anyway.

And in some cases, well over 100, especially in the West.

I-5/(Former) US 99 (104)
I-15/(Former) US 91 (106)
I-25/US 87 (112)

And those are just a few examples off the top of my head.

[tidecat]

One of the largest over 100 is in Kentucky and West Virginia:

I-64 + US 60 = 124

[rawmustard]

Of course that's cherry picking just 2 routes from a multi-multiplex. I wonder what the maximum "total" is (will be) for any stretch of 465. INDOT piggybacks a lot of highways on the outer belt. I'm betting it's in the 700 or 800 range. Maybe I'll get time later to figure it out.

I'm coming up with 1218 for the stretch from Washington Street to Brookville Road once I-69 gets added (currently it's 1149). You're not going to get a higher total with 74 because it joins as 421 leaves.

[theline]

^^ Thanks, rawmustard. I knew if I was lazy enough, somebody would do the math for me. That's a lot higher that I thought, but I forgot about 421. I thought somewhere along the I-74 multiplex would get the highest total, but 421 definitely beats it.

[roadman65]

This is supposed to be about ending in 100.  Yes US 31 and future I-69 will do that alone, just as US 6 and I-94 do currently near Chicago.

Not t add up more concurrency totals or to add on lets the the I-80 and US 41 to the mix to make the I-94 and US 6 concurrency more.  Yes some of us think the OP means solo two or three route concurrencies that add up to 100, which he does want.  However, whether US 6 with I-94 and US 31 with Future I-69 is paired with others such, still regardless the two routes concurred still add up to one hundred and they still are together despite other route numbers added to the mix.

[Henry]

I compiled a list of every Interstate in existence and its theoretical US counterpart, and here's what I came up with:

I-2/US 98 (former in TX; latter east of Mississippi)
I-4/US 96 (former in FL; latter in TX)
I-5/US 95 (former completely west of latter)
I-8/US 92 (former in CA/AZ; latter in FL)
I-10/US 90
I-12/US 88 (latter does not exist)
I-15/US 85 (former completely west of latter)
I-16/US 84
I-17/US 83 (former completely west of latter)
I-19/US 81 (former completely west of latter)
I-20/US 80
I-22/US 78
I-24/US 76
I-25/US 75 (former completely west of latter)
I-26/US 74
I-27/US 73 (former completely west of latter)
I-29/US 71
I-30/US 70
I-35/US 65
I-37/US 63 (former completely west of latter)
I-39/US 61 (former completely east of latter)
I-40/US 60
I-41/US 59 (former completely east of latter)
I-43/US 57 (former in WI; latter in TX)
I-44/US 56
I-45/US 55 (former in TX; latter existed in MN)
I-49/US 51 (former completely west of latter)
I-55/US 45
I-57/US 43 (former completely west of latter)
I-59/US 41
I-64/US 36 (former completely south of latter)
I-65/US 35 (former completely west of latter)
I-66/US 34 (former completely south of latter)
I-68/US 32 (former in MD/WV; latter in IL)
I-69/US 31
I-70/US 30
I-71/US 29 (former completely west of latter)
I-72/US 28 (former in IL; latter existed in OR)
I-73/US 27 (former completely east of latter)
I-74/US 26 (former in IA/IL/IN/OH/NC; latter in OR/ID/NE)
I-75/US 25
I-76/US 24
I-77/US 23 (former completely east of latter)
I-78/US 22
I-79/US 21 (former completely east of latter)
I-80/US 20
I-81/US 19
I-82/US 18 (former in WA/OR; latter in SD/WY)
I-83/US 17 (former in MD/PA; latter in VA/NC/SC/GA/FL)
I-84/US 16 (former in OR/ID/UT/PA/NY/CT/MA; latter in SD/WY)
I-85/US 15
I-86/US 14 (former in ID/PA/NY; latter in IL/MN/ND/MT)
I-87/US 13 (former in NY; latter in PA/DE/MD/VA/NC)
I-88/US 12
I-89/US 11 (former completely east of latter)
I-90/US 10
I-91/US 9 (former completely east of latter)
I-93/US 7 (former completely east of latter)
I-94/US 6
I-95/US 5
I-96/US 4 (former in MI; latter in NY/VT/NH)
I-97/US 3 (former in MD; latter in MA/NH/VT)
I-99/US 1 (former completely west of latter)

[KCRoadFan]

I-87/US 13 (former in NY; latter in PA/DE/MD/VA/NC)

As for the "new I-87"  in NC - how close is that one to US 13? (Pardon the bump.)

[Mapmikey]

I-87/US 13 (former in NY; latter in PA/DE/MD/VA/NC)

As for the "new I-87"  in NC - how close is that one to US 13? (Pardon the bump.)

There will be an overlay of I-87 and US 13 in NC, though US 17 will also be on it throughout that concurrency and for a short stretch also US 64.

[SkyPesos]

I began noticing how multiplexed Interstate and US highway routes often have complementary numbers that usually add up to between 90-110, but sometimes settle right on 100.

Lots of 110s too for paired Interstate/US routes

I-90/US 20
I-80/US 30
I-70/US 40
I-40/US 70

[JayhawkCO]

I began noticing how multiplexed Interstate and US highway routes often have complementary numbers that usually add up to between 90-110, but sometimes settle right on 100.

Lots of 110s too for paired Interstate/US routes

I-90/US 20
I-80/US 30
I-70/US 40
I-40/US 70

I-25/US85 off the top of my head too.

[7/8]

Some close ones in Ontario:
Highway 10 and 89 in Shelburne (= 99)
Highway 41 and 60 in Eganville (= 101)
Highway 28 and 62 in Bancroft (= 90)

[DTComposer]

We need an I(minus)-1 on the Oregon Coast to go with US 101...LOL!  I guess we'll build it offshore.

Rick

[channelling FritzOwl]
My plans have Interstate -1 connecting Whittier, AK and Cabo San Lucas via Monatgue Island, Kayak Island, Sitka, Moresby Island, Tofino, multiplexing with Interstate 1 (US-101) between Kalaloch and Eureka (to get your century multiplex), the Farrallones, the Channel Islands (with Interstate -301 as a spur from Avalon to Long Beach), and Isla Guadalupe.

This will greatly reduce traffic in this corridor and will be a cheaper alternative to all of the shipping lanes that currently exist.
[/FritzOwl]