On a recent drive from Ohio to South Carolina, 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.
For example:
In NC, I-77 and US 21 = 98
In NC, I-85 and US 15 are multiplexed near Raleigh = 100
In KY, I-75 and US 25 share a bridge south of Lexington = 100
In OH, I-76 and US 224= 300
OH, I-475 + US 23 = 498
These are just a few of many. Do you know any multiplexed "century" routes?
A long time ago: US 10 and I-90.
BC 99 and BC 1 (TCH) in North Vancouver.
WA has a lot of missing 2dis (from 41 onwards), so it's really hard to find century multiplexes. Adding up to 1,000 could be possible.
I-20 and US 80, along with I-10 and US 90.
Alabama and Mississippi: I-22 and US 78
I-69 and US 31 once the NAFTA interstate gets signed along the I-465 Beltway.
We need an I(minus)-1 on the Oregon Coast to go with US 101...LOL! I guess we'll build it offshore.
Rick
I-97 and BUS MD 3. Took me some head scratching to come up with that one.
Wisconsin: I-39/U.S. 10/U.S. 51 in the Stevens Point Area for a triplex that equals 100
Quote from: Charles2 on September 08, 2015, 11:48:59 PM
Alabama and Mississippi: I-22 and US 78
I-78 and US 22 in Pennsylvania.
Also a former multiplex- I-35 and US 65 in Minnesota between St Paul and Albert Lea.
I-91 and US 5...almost. :D
Quote from: roadman65 on September 09, 2015, 12:03:54 AM
I-69 and US 31 once the NAFTA interstate gets signed along the I-465 Beltway.
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-85 and US 15
Honorable mention: I-40 Bus and US 60
Former: I-75 and US 25
Then there's I-70 and US 30 in Breezewood
Mike
I-29 and US 71.
I-26 and US 74 in western North Carolina.
US 6 and I-94 in IN/IL. I believe that 6 is the lowest numbered US Route to have a "century multiplex"
Quote from: cabiness42 on September 09, 2015, 03:37:08 PM
US 6 and I-94 in IN/IL. I believe that 6 is the lowest numbered US Route to have a "century multiplex"
Yep.
Quote from: Bruce on September 08, 2015, 11:24:04 PM
WA has a lot of missing 2dis (from 41 onwards), so it's really hard to find century multiplexes. Adding up to 1,000 could be possible.
Nope. You actually run into the same problem. Lots of numbers in the lower half of each hundred, not so many in the upper half. And when you do have more "upper half" numbers in the 100s and 200s, you have very few corresponding numbers in the 700s and 800s.
I think the only current pair that adds up to 1,000 is 401 and 599. Which are pretty far from each other geographically.
Historically, there was an SR 294 outside Spokane until the 70s, but that's even further from SR 706. Also, for a couple of years in the 60s, you could have paired 169/831 and 167/833. But those were still separated by 100+ miles.
Back on topic, there are actually more existing century pairs than "millenium" pairs in Washington, but again no multiplexes. SR 18/I-82, SR 10/I-90, SR 8/SR 92, SR 4/SR 96, and SR 3/US 97. 10/90 is obviously the closest, but SR 10 ends just short of I-90 on each side, so they don't even intersect, much less intersect.
ETA: I forgot to account for numbers ≤100 when looking for "millenium" pairs. SR 900/SR 100 and SR 903/US 97 exist, as well as three more historical pairs. Still no intersections or multiplexes, but at least 903 and 97 are both in the same part of the state.
I-35 and US 65 formerly did before 65 was eliminated north of Albert Lea, MN.
Quote from: Mapmikey on September 09, 2015, 01:23:55 PM
Then there's I-70 and US 30 in Breezewood
Mike
Technically I-70 is discontinuous, so no.
Also, the 2dI+2dUS examples are boring.
Quote from: TheHighwayMan394 on September 09, 2015, 07:35:48 PM
I-35 and US 65 formerly did before 65 was eliminated north of Albert Lea, MN.
Already said that.
Quote from: national highway 1 on September 09, 2015, 03:11:20 AM
Quote from: Charles2 on September 08, 2015, 11:48:59 PM
Alabama and Mississippi: I-22 and US 78
I-78 and US 22 in Pennsylvania.
Also a former multiplex- I-35 and US 65 in Minnesota between St Paul and Albert Lea.
I-30 and US 70 near Little Rock, AR.
Missouri: I-29 and US 71, from the KC metro to St. Joseph.
Quote from: national highway 1 on September 09, 2015, 09:28:38 PM
Quote from: TheHighwayMan394 on September 09, 2015, 07:35:48 PM
I-35 and US 65 formerly did before 65 was eliminated north of Albert Lea, MN.
Already said that.
Quote from: national highway 1 on September 09, 2015, 03:11:20 AM
Quote from: Charles2 on September 08, 2015, 11:48:59 PM
Alabama and Mississippi: I-22 and US 78
I-78 and US 22 in Pennsylvania.
Also a former multiplex- I-35 and US 65 in Minnesota between St Paul and Albert Lea.
Don't really care. Does it really need to be pointed out that I repeat posted?
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.
Thanks everyone - I was aware of the contrasting numbering for US and Interstate routes, and I figured a lot of x5 and x0 routes would add up to 100 - what surprises me are the other examples, and not just in a diagonal path from NE to SW across the country.
Quote from: Road Hog on September 10, 2015, 01:39:05 AM
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.
One of the largest over 100 is in Kentucky and West Virginia:
I-64 + US 60 = 124
Quote from: theline on September 09, 2015, 01:02:04 PM
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.
^^ 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.
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.
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)
Quote from: Henry on September 11, 2015, 11:29:12 AM
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.)
Quote from: KCRoadFan on February 09, 2022, 05:57:22 PM
Quote from: Henry on September 11, 2015, 11:29:12 AM
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.
Quote from: westerninterloper on September 08, 2015, 11:16:42 PM
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
Quote from: SkyPesos on February 10, 2022, 02:47:29 PM
Quote from: westerninterloper on September 08, 2015, 11:16:42 PM
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.
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)
Quote from: nexus73 on September 09, 2015, 12:49:31 AM
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]