Consecutive Route Changes In Numerical Order...

[thenetwork]

This sounds more complicated than it actually is.  Here is the assignment:

Pick any state, or the state in which you live, what is the most number of connecting route changes you can make in consecutive numerical order, using only State, US & Interstate Routes?? 

For example, in Ohio (circa the 1960s*):

• Starting on OH-18 to Republic, OH
• North on OH-19 to Fremont, OH
• East on US-20 to Cleveland, OH
• South on US-21* (*-- Based on old Northern Terminus @ Public Square in Cleveland and following old US-21 alignment) to Cambridge, OH
• West on US-22 to Circleville, OH
• North on US-23 to Maumee, OH
• East on US-24 to Toledo
• North on US-25 in Toledo (in the 1960's, US-24 & US-25 multiplexed together at the intersection of US-23 at the time in Downtown Maumee. Since they split northeast of Maumee, I count them as two.

TOTAL CONSECUTIVE ROUTES: 8

Have fun with this one... 8 could very well be hard to beat. 

[corco]

I really thought i'd be able to do better in Washington, but the best I can come up with is

Washington 100 to US-101
US-101 to Washington 102

there's one other instance of 3 that i can think of- SR 4 to I-5 to SR 6, and 525 -> 526 -> 527

Wyoming is pretty bleak too- there's one instance of three I can figure out

WYO 190 to WYO 191, WYO 191 to WYO 192

[agentsteel53]

I believe the longest US run (counting some decommissioned routes) is in the 60s

59 to 60, Oklahoma
60 to 61 to 62, Missouri
62 to 63, Missouri
63 to 64, Arkansas
64 to 65, Arkansas
65 to 66, Missouri
66 to 67, Missouri

can't do 58 or 68, but that is 9 consecutive routes.  Are there any chains that are longer? 

[Alps]

NJ has gaps in consecutive routes, so the best isn't all that great: 33 east-34 south-35 north-36 north.  Delaware doesn't have any instance of even three in a row.  Alaska - 1 east-2 north-3 south.

[agentsteel53]

interstates have so many gaps in them, that the first instance of even two consecutive interstates meeting is ... 64 and 65!  With no 66 anywhere nearby, and no 67 at all, that pattern peters out rather quickly.  

69-70-71 is our first triple... when 69 gets built, anyway!

73-74-75 is another potential, except who the Hell knows where 73 and 74 are these days.

79-80-81 is quite legitimate.

and that's all, folks!  Had they built I-92 over the entire US-4 corridor, we could've had 90-91-92-93.

so, as it seems, the number of the counting shall be ... three.

[Kniwt]

Looks like I can do 7 in a row in Indiana:

US 35 northwest from Ohio line to US 36
US 36 to SR 37 (I-465 multiplex)
SR 37 north to SR 38
SR 38 west to SR 39
SR 39 south to US 40
US 40 west to US 41

And if it weren't for the decommissioning of SR 42 within Terre Haute, they'd link there as well.
And if SR 43 were still co-signed with US 231, they'd link there.

Indiana's numbering system appears to be among the best for this type of thing. Lots of 5s and 6s, too.

[TheStranger]

California has only had several examples of three consecutive routes:

Route 49 with US 50 at Placerville
US 50 with unsigned Route 51 (Business 80) in Sacramento

pre-1964...
Route 78 with Route 79 at Julian
Route 79 with what was US 80 (now I-8) in Descanso

[Scott5114]

The best I can find in OK is 1->2->3, which is kind of neat because 1/2 concur and 2 ends at 3. Both of the 4s are too far apart to connect to. 5->6 connect, but 7 is too far away. 8->9 connect, but likewise 10 doesn't connect to 9 anywhere. 10 and 11 never link up. 12 and 13 don't exist. 14 is a short little connector in Woods County that only intersects US routes (and 45). And so on down the line.

[rawmustard]

The only current examples between trunklines in Michigan are M-32 and M-33, M-46 and M-47, and M-139 and M-140. Even considering historical examples, I'm hard-pressed to find one that is more than two consecutive. Of course, that's not considering any of the counties which still post numbers for their roads, but even then it's doubtful you could create a long chain of them.

[mightyace]

interstates have so many gaps in them, that the first instance of even two consecutive interstates meeting is ... 64 and 65!  With no 66 anywhere nearby, and no 67 at all, that pattern peters out rather quickly.

If Kentucky's pipe dream ever becomes a reality then you could have an I-64-65-66 routing.

[PAHighways]

I-79 -> I-80 -> I-81 for a roundabout way to avoid the Turnpike between Pittsburgh to Harrisburg

[english si]

In the UK, you can do M4-M5-M6-A7-A8-M9 (grabbing all three British countries), and before they declassified all roads in the City of London, you could have done A2-A3-A4-M5-M6-A7-A8-M9.

It used to be the case that you could do Edinburgh to Ayr (via Gretna) via A70-A71-A72-A73-A74-A75-A76-A77-A78-A79, which is ten, but the A74 motorway upgrades means that you can't do this anymore. This leaves A74(M)-A75-A76-A77-A78-A79 for another 6.

[Kniwt]

Alberta has TC 1 > PR 2 > PR 3 > PR 4 > PR 5 > PR 6.

[Bickendan]

Not seeing any in Oregon, though it may be possible with the underlying Highway System. That'll take some research.

[luokou]

Not seeing any in Oregon, though it may be possible with the underlying Highway System. That'll take some research.

One that comes to mind: OR 212 -> OR 213 -> OR 214
If OR 212 was needlessly multiplexed to Sandy, you could add OR 211 to the chain (though OR 213 does intersect OR 211 in Molalla, just out of order). Furthermore, had the Cascades Hwy south of Silverton retained its OR 215 number, you could have at least a 4-chain with 212-213-214-215.

Going by unsigned highway numbers: 454 -> 453 -> 452 (all near Adrian) except you'd have to double-back on 454 just to get to 452.

[mrcontroversy]

Kansas: From K-23 at Hoxie, west on US-24 to K-25 at Colby;
Multi-state: From K-68 at Ottawa, east to US-69, north to I-70, cross into Missouri, south on US-71.

[Kniwt]

Ooooh, I think we might have best yet in Alabama with *10*, thanks to the practice of co-signing state and U.S. routes.

SR 1 (US 431) meets SR 2 (US 72) in Huntsville
SR 2 meets SR 3 near Athens
SR 3 (US 31) meets SR 4 (US 78) in Birmingham
SR 4 runs concurrent with SR 5 in Birmingham
SR 5 meets SR 6 (US 82) near Centreville
SR 6 meets SR 7 (US 11) in Tuscaloosa
SR 7 meets SR 8 (US 80) just before the Mississippi state line
SR 8 meets SR 9 (US 331) in Montgomery
SR 9 meets SR 10 (US 29) in Luverne

The chain ends because US 11 is about 15 miles away.

[Andrew T.]

Until 1974, a two-county swath of US 19 in West Virginia was signed concurrently with US 21.  With that in mind, you could take US 19 south from Beckley to Princeton, take a loop around the point where both it and WV 20 circle the courthouse, then head back north to Beckley via US 21 on the exact same road!

[Scott5114]

In the UK, you can do M4-M5-M6-A7-A8-M9 (grabbing all three British countries), and before they declassified all roads in the City of London, you could have done A2-A3-A4-M5-M6-A7-A8-M9.

It used to be the case that you could do Edinburgh to Ayr (via Gretna) via A70-A71-A72-A73-A74-A75-A76-A77-A78-A79, which is ten, but the A74 motorway upgrades means that you can't do this anymore. This leaves A74(M)-A75-A76-A77-A78-A79 for another 6.

I think Britain would be particularly good for this sort of thing because of the first-digit zoning system, which isn't used anywhere in the US.

[english si]

oh yes Scott, that helps, but actually it's quite rare to even get four consecutive numbers in a row - other than these 2 sixes, there's only one or two. Lots of threes though. A major part of the problem is not having any multiplexes - I looked and you couldn't get the A70 in the big trip across Scotland (but 9 isn't to be sniffed at), due to the A71 disappearing under the A73 for a mile. It's normally the case that, while road numbers are numbered sequentially and all that, they don't often touch each other, but are just nearby (plus the huge amount of renumbering in 1935 killed off a lot of the logic of the original system).

A grid might fair better as odds and evens are designed to intersect with each other and increase in sequence. - you could have (starting at 1 and 4) north on 1, east on 2, south on 3, east on 4, south on 5, east on 6 and so on. Shame the Germans didn't finish A4 or A5 to plan, or the A8 and A9 in Munich. Because you can (sort of) do what I suggested if they did (travel on A1, west on A2, south on A3, east on A4, south on A5, east on A6, south on A7, east on A8, north on A9, round Berlin on A10 and north on A11 would have been doable). You can do 1-2-3-4 and 5-6-7-8 today, but not finishing the plans didn't help!

Ireland fails poorly. The best I've found is, formerly, you could go Foxford - Ballina - Westport - Roscommon - Boyle on N58-N59-N60-N61, but the N26 got created and the N5 extended, so it can't be done now. Actually, just thought - you can go N13-N14-N15-N16 zigzagging from coast to border, or M20-N21-N22-N23 from Limerick to a loop near Tralee. That's the best - 2 fours.

Northern Ireland is pretty much random when it comes to numbering. The best I can do is A20-A21-A22, or A4-A5-A6 (the A3 would have got in on the action, but couldn't due to the A4 getting piggybacked by the M1. There's not even another three.

[hbelkins]

Closest Kentucky comes is 9-10-11 in the Maysville area. KY 8 also serves this area but does not intersect with KY 9.

In West Virginia, you get close with US 60-WV 61-WV 62 in the South Charleston area, but no cigar.

[thenetwork]

Best I could find in Colorado was 4, and a very easy 4 at that:

• I-25 South (Unsigned US-85) to Exit 182 in Castle Rock
• CO-86 East under I-25 Bridge
• I-25 North (Unsigned US-87) to Exit 197 in Centennial
• CO-88 West joins the I-25/US-87 multiplex.

[AZDude]

Only one I can think of in Arizona was AZ 88 and US 89 when US 89 used to pass through Mesa, AZ. 

[kurumi]

Connecticut:
1 - 2 - 3, 70 - 71 - 72, 79 - 80 - 81. Long ago, when CT 4 ended at US 5 in Hartford, you could do 4 -5 - 6 - 7.

[WNYroadgeek]

I can't think of any in New York longer than NY 18 (Hamlin) -> NY 19 (Pavilion) -> US 20 (Canandaigua) -> NY 21