The Furthest Into A State Can You Go On An Interstate....

[thenetwork]

...before you encounter your first exit with a US or State Route or other Interstate?


Due to decommissioning of several routes over the decades, you now have to go all the way to Exit 20 to reach the first shielded route (I-275) and Exit 28 for the first state route (M-85).

Any other noteworthy distances into a state before reaching the first overall route &/or state route?

[The High Plains Traveler]

I thought to look at this since I drove it in the past two weeks. Entering Montana on I-90 WB from Wyoming you go about 40 miles to the first exit with a numbered route (U.S. 212).

[iowahighways]

The winner for Iowa is I-35, heading south from Minnesota: 15 miles until you reach IA 9. (The first exit used to be IA 105, but it has since been demoted to a county road.)

I-29 and I-80 both intersect state-maintained highways within a mile of entering Iowa at both of their ends, and I-35 intersects US 69 at the Iowa/Missouri border.

[Duke87]

I-90 makes it 33 miles into Montana before the exit for MT 135.
I-15 in the same state has 44 miles before MT 324.

Of course, we also have to consider that this can be measured at the end of the state as well as the beginning: I-84 in Idaho goes 53.5 miles from its junction with I-86 to the Utah state line without directly intersecting another signed numbered highway.


Also, I-A1 (signed as AK 2 on this segment) is a good 77 miles from the border with Yukon at Alcan to the intersection with AK 5 in Tetlin Junction. But that's not an "exit" so it doesn't count.

[mgk920]

The first interchanges encountered on all of the state-line crossing interstates in Wisconsin, other than for I-90 from the west, are with numbered state highways.

For WI, then, the deepest such first encounter is US 53/WI 35 (interchange 3), on I-90 in La Crosse.  Interchange 2 is a local street.

Mike

[getemngo]

It's amazing (or perhaps not) how many Interstates are disqualified because their very first exit in a state is with a numbered highway.

The longest I could find not already mentioned here is I-15, which intersects nothing but county roads in its 29.43 miles through Arizona.  Colorado's record is pretty high too... on I-25, it's about 21 miles from the Wyoming state line to SH 1.

[corco]

I-15 in the same state has 44 miles before MT 324.

Close, except exit 0 is a state highway!

[NE2]

Interesting related question: what's the farthest between exits for state highways? I think Florida's Turnpike is still the longest between exits, period (49 miles if you get on northbound at Yeehaw Junction), but there have to be longer state highway examples out west.

[getemngo]

Interesting related question: what's the farthest between exits for state highways? I think Florida's Turnpike is still the longest between exits, period (49 miles if you get on northbound at Yeehaw Junction), but there have to be longer state highway examples out west.

I-80 in Wyoming has a 57-mile stretch, from WYO 377 at Point of Rocks (exit 130) to WYO 789 (exit 187). And exit 130 isn't signed as WYO 377, so to motorists it looks like 65 miles, with the western end being exit 122.

[Rover_0]

Some from Utah:

--US Route: I-15 from Arizona state line to US-50, 178 miles
--Interstate: I-70 from Colorado state line to I-15, 232 miles
--State Route: I-70 from Colorado state line to UT-128, 27 miles

[froggie]

If we're talking about state+ highways and not numbered highways in general, then Minnesota's longest from the state line is I-35 from Iowa, where it's only 8 miles to the US 65 exit in southeast Albert Lea.  All the other Interstate crossings have an interchange with a state or US route within a mile-and-a-half, 3 of those within only a half-mile of the state line (I-94 Moorhead, I-94 Afton, I-90 La Crescent).

Then there's I-10 in Alabama where, coming from Florida, you go 14 miles before you even get to an exit (Exit 53/CR 64).  And add another 9 miles before you cross a state highway (Exit 44/AL 59).

[DTComposer]

In California:

On I-15 it's about 50 miles from the Nevada state line to CA-127.

On the second question: on I-40, it's 133 miles between I-15 and US-95.

[Brandon]

In Illinois, it's pretty pathetic.  Most meet state or US routes at the border or within a few miles.  The winner is I-74 near Danville at 5 miles for US-136/IL-1.

[Zeffy]

In Illinois, it's pretty pathetic.  Most meet state or US routes at the border or within a few miles.

Ditto for New Jersey. I think coming from PA on I-80 EB wins for New Jersey, at a whopping 4¼ miles. Then you have I-78 from PA, which is almost 4 miles.

[sandwalk]

From what I could see, Ohio's is along I-76 near Youngstown.  The first interchange, with I-680, is 7 miles from the Pennsylvania border.  Actually, there is no exit in the 16 mile stretch between I-376 in PA and I-680 in OH. Makes sense though....since I-76 is a turnpike.

For a non-tolled interstate, it would be I-74 near Cincinnati.  Its interchange with I-275 is 5.5 miles from the Indiana border.

*Fun fact*
The first (or last, depending on your direction of travel) interchange along I-80, I-70, I-470, and I-77 in eastern Ohio is with State Route 7 (7A, in the case of I-470).

[agentsteel53]

I wonder what it is for Kentucky.  can't be more than 5 miles with their thousands of state routes.

[OracleUsr]

NC has 20 miles (I-40 entering from the west, for US 276)

[formulanone]

Interesting related question: what's the farthest between exits for state highways?

I-75 along Alligator Alley: US 27 (FL 25) - Exit 23 / Skip CR 833 / then FL 29 - Exit 80.

So, 57 miles. 

Then there's I-10 in Alabama where, coming from Florida, you go 14 miles before you even get to an exit (Exit 53/CR 64).  And add another 9 miles before you cross a state highway (Exit 44/AL 59).

There's that suspension of disbelief the first time I crossed into Alabama via I-10, because there seemed to be no exits...

[Brandon]

Interesting related question: what's the farthest between exits for state highways?

In Illinois, it is I-74 from Exit 54 (US-150, Knoxville) to Exit 87 (I-474/IL-6, Peoria), a total of 33 miles.
Other stretches come close though.
I-88 from Exit 78 (I-39/US-51) to Exit 109 (IL-47), 31 miles.
I-72 from Exit 103 (I-55) to Exit 133 (US-36/51), 30 miles.
I-90 from I-39/US-51 to US-20, 25 miles.

[Thing 342]

On I-95 in Virginia, you can go nearly 31 miles from the NC border without crossing a primary route.

[hbelkins]

I wonder what it is for Kentucky.  can't be more than 5 miles with their thousands of state routes.

My guess would be 11 miles, since the first exit northbound on I-75 is Exit 11 for KY 92 at Williamsburg.

[dfilpus]

On I-95 in Virginia, you can go nearly 31 miles from the NC border without crossing a primary route.

US 58, at 11 miles, and US 301, at 17 miles, are primary routes.

[getemngo]

Interesting related question: what's the farthest between exits for state highways? I think Florida's Turnpike is still the longest between exits, period (49 miles if you get on northbound at Yeehaw Junction), but there have to be longer state highway examples out west.

I-80 in Wyoming has a 57-mile stretch, from WYO 377 at Point of Rocks (exit 130) to WYO 789 (exit 187). And exit 130 isn't signed as WYO 377, so to motorists it looks like 65 miles, with the western end being exit 122.

I-75 along Alligator Alley: US 27 (FL 25) - Exit 23 / Skip CR 833 / then FL 29 - Exit 80.

So, 57 miles.

I put each of our answers into Google Maps and got 56.2 miles for both of them. This is a mighty close one...

[tdindy88]

In a similar fashion as Ohio's example, the Indiana Toll Road (I-80/I-90) goes 13 miles from the Ohio state line before hitting its first interchange at I-69. Then it's 23 miles between the I-69 exit and the SR 9 exit, marking what should be the longest distance between exits at all in the entire state on any freeway.

[TheStranger]

I wonder what it is for Kentucky.  can't be more than 5 miles with their thousands of state routes.

11 miles on I-75 from Tennessee state line to the SPUI at KY 92 in Williamsburg.