Roads that intersect both the preceding and following numbers within a state

[KCRoadFan]

I just thought about how in Sikeston, MO, US 61 intersects with both US 60 and US 62. In addition, US 60 intersects MO 59 near Neosho.

Throughout the country, what other roads are there that, within a given state, intersect both with a road of the preceding number (that is to say, the number minus one), as well as the following number (the number plus one)? In other words: If x is the number of a road, what roads intersect with roads numbered x-1 *and* x+1 within the same state?

[hotdogPi]

New Hampshire has 9-10-11-12, plus 8 and 13 if you cross into Vermont and Massachusetts, respectively (9 and 12 keep their numbers across state lines).

[NWI_Irish96]

Indiana:

IN 13-IN 14-IN 15-IN 16-IN 17
IN 18-IN 19-US 20
IN 26-US 27-IN 28-IN 29
US 30-US 31-IN 32
US 35-US 36-IN 37-IN 38-IN 39-US 40-US 41

[mukade]

Indiana:

IN 13-IN 14-IN 15-IN 16-IN 17
IN 18-IN 19-US 20
IN 26-US 27-IN 28-IN 29
US 30-US 31-IN 32
US 35-US 36-IN 37-IN 38-IN 39-US 40-US 41

Two more Indiana ones:
- SR 58 intersects SR 57 and SR 59
- SR 65 intersects SR 66 and SR 64 (plus I-64 as a bonus)

[gonealookin]

Nevada clusters similar state highway numbers.  It looks like there are three examples:

1.  In Lovelock, SR 398 intersects both SR 397 and SR 399 (and SR 396 too).
2.  Along Pyramid Lake north of Reno, SR 446 connects SR 445 to the west and SR 447 to the east.
3.  In the Smith Valley, SR 824's northwest terminus is at SR 823, and SR 825 is a short spur road off of SR 824.

There are some other close ones which don't quite qualify; for example in the Mt. Charleston area outside Las Vegas, SR 158 is the connector between SR 156 and SR 157.

[ran4sh]

I-80 intersects I-79 and I-81 in Pennsylvania

[Crown Victoria]

I-80 intersects I-79 and I-81 in Pennsylvania

There's also US 30, which intersects the southern PA 29's southern terminus in Chester County, and PA 31's eastern terminus in Bedford County.

In addition, PA 75 meets PA 74's northern terminus in Juniata County, and intersects I-76 (PA Turnpike) at the Turnpike's Willow Hill interchange in Franklin County.

[7/8]

Ontario:
- 6
- 7
- 401
I'm not sure if there's any for Secondary Highways.

[SkyPesos]

I-80 intersects I-79 and I-81 in Pennsylvania

In the next year or two, I-70 will be the second interstate to intersect both the preceding and following interstate numbers, with I-69 meeting it via I-465.

[hbelkins]

In Ohio, US 23 intersects both US 22 and US 24.

[JayhawkCO]

In Colorado:

US24->I-25->CO26
US85->CO86->US87->CO88

Specifically, CO86 intersects US85 and US87 at the same time.

[US 89]

In Utah:

SR 90 intersects US 89 and US 91 east of Brigham City (and in the same place, since 89/91 are concurrent through there)

SR 172 intersects SR 171 and SR 173 three miles apart in West Valley

[kurumi]

In Connecticut:
30 - 31 - 32 (not an original cluster. 32 was there first as a NE interstate; then 31 replaced old US 6; then 30 replaced old CT 15)
70 - 71 - 72
79 - 80 - 81 (from 1932)

[SEWIGuy]

In Wisconsin, a state without a grid of any sort, WI-22 intersects with both WI-21 in Wautoma and WI-23 in Montello.  About 20 miles apart.

[MATraveler128]

US 5, US 6, US 7, CT 8, CT 9, and CT 10 in Connecticut. Is that the record?

[hotdogPi]

US 5, US 6, US 7, and CT 8 in Connecticut.

US 7 never touches CT 8 or its extension in MA or VT.

[JayhawkCO]

Alaska:

AK1->AK2->AK3

[MATraveler128]

US 5, US 6, US 7, and CT 8 in Connecticut.

US 7 never touches CT 8 or its extension in MA or VT.

Oops, I guess I missed that. Also, there's MA 2, US 3, and MA 4 in Massachusetts.

[Mapmikey]

It appears Virginia has just one current example:  VA 2

North Carolina:  NC 96

South Carolina:  don't see one

[DTComposer]

There are some close calls in California, but I think the closest it gets is CA-79, which intersects CA-78, and terminates at historical US-80.

[MATraveler128]

Rhode Island, RI 115, RI 116, RI 117

Maine, ME 15, ME 16, ME 17

I don't think Vermont has one, the closest I found was VT 3, US 4, and US 5, but VT 3 ends at US 4 Business, which doesn't come near US 5. Actually, it used to count because Business 4 used to be the mainline US 4.

[hbelkins]

Historic example in Kentucky. Before KY 35 south of its current terminus became US 127, KY 34 intersected both KY 33 and KY 35 in downtown Danville.

[frankenroad]

In Ohio, US 23 intersects both US 22 and US 24.

and before the de-commissioning of US-21 and US-25 in Ohio, there were also
20-21-22
23-24-25

with the way Ohio clusters state routes, I have to assume there are several examples;
two I can think of off the top of my head are OH-126-US-127-OH-128 and US-127-OH-128-OH-129

[TheHighwayMan3561]

MN

US 14: MN 13 and MN 15
MN 28: MN 27 and MN 29 (27-28-29 is an intersection chain)

[thspfc]

WI-32 intersects WI-31 and WI-33

WI-64 intersects US-63 and WI-65

US-12 intersects WI-11 and WI-13, which is weird to think about