Dual Purpose Highways

[nwi_navigator_1181]

Good evening.

There are some roads that, while not explicitly stated, serve a dual purpose. What I mean is this; one stretch of freeway covers two long-range destinations going two different directions.

Example (and the inspiration for this thread): in another topic I discussed, a poster mentioned a stretch of I-57 (namely, the portion between I-64 - concurrency included - and I-24) serving two purposes: connecting those in Chicagoland and the remote northeastern areas of Illinois to the mid-south and connecting those in the Midwest (especially from Kansas City and St. Louis) to the southeast. (Of course, the inverse can be said as well.)

One portion of highway simultaneously serving two different regions. Do you have any other examples? Share them here.

As always, thank you in advance for your responses.

[webny99]

Would multiplexes be included in what you're looking for? If so, most of the longer ones would qualify, such as I-64/I-81 and I-20/I-59.

The two most prominent single-route examples in upstate New York would be:
(1) I-87 between I-90 and the Berkshire Spur, which carries both Boston-Buffalo and NYC-Montreal traffic
(2) I-86 between US 15 and I-390, which carries both Rochester-Baltimore and Buffalo/Canada-NYC traffic.

[I-55]

I-24 in Chattanooga carrying Knoxville-Birmingham traffic and Nashville-Atlanta traffic.

[nwi_navigator_1181]

Would multiplexes be included in what you're looking for? If so, most of the longer ones would qualify, such as I-64/I-81 and I-20/I-59.

As long as they share the same pavement, I will be more than glad to allow it. Let's just get I-80/94, I-80/90, and both runs of I-90/94 out of the way.

[SkyPesos]

I-65 between Louisville and Nashville carries traffic from Chicago to states like Georgia and Florida, and also carries traffic from Ohio, Michigan and parts of the Northeast to Texas.

[nwi_navigator_1181]

I-65 between Louisville and Nashville carries traffic from Chicago to states like Georgia and Florida, and also carries traffic from Ohio, Michigan and parts of the Northeast to Texas.

This one is vastly understated and thought of very little by me, but makes perfect sense.

If I were coming from eastern Michigan (Mackinaw City, Saginaw, Detroit) or western Ohio (Dayton, Cincinnati), it would be quicker to use I-65, via I-71/75, to get to I-40 and access Texas, whether by staying the course or picking up I-30 in Little Rock.

Explains the multitude of Texas license plates I've seen between Bowling Green and Parsons in my former reunion trips.

[US 89]

I mean...just about every interstate concurrency out there?

[kphoger]

Most 'good' examples I can think of exist in or around cities–that is, where highways naturally converge and diverge.  I'm still hunting around the map for good, long-distance, rural examples...

* kphoger does the aforementioned hunting around the map...

OK, how about this one:  I-70 between Effingham and Indianapolis.
  Oklahoma City/Albuquerque ↔ Washington/New York
  Dallas/Houston ↔ Detroit/Toronto

[snowc]

Good example: I-81 in Scranton. Carries the Scranton traffic and also the Binghamton NY traffic.

[ethanhopkin14]

I think I have this correct.  I am thinking about I-30.  It is obviously first of all in it's form a connection from the Metroplex to Little Rock.  It is the shortest I-X0, but plays a huge roll.  It I also a connection from I-20 to I-40.  Bigger picture, since I-20 is spawn off of I-10, it is a connection from Los Angeles and Phoenix to Memphis, Nashville and Raleigh-Durham.  You could even say its one of the connection from Los Angeles to New York.  Considering it's short length, I-30 plays a major role in west-east travel. 

[webny99]

Good example: I-81 in Scranton. Carries the Scranton traffic and also the Binghamton NY traffic.

I-81 between Scranton and Binghamton not only qualifies, but blows everything else out of the water.

You've got:

NYC-Toronto
NYC-Buffalo
NYC-Rochester
NYC-Syracuse
NYC-Ottawa

Philadelphia-Toronto
Philadelphia-Buffalo
Philadelphia-Rochester
Philadelphia-Syracuse
Philadelphia-Ottawa

Allentown-Toronto
Allentown-Buffalo
Allentown-Rochester
Allentown-Syracuse
Allentown-Ottawa

Harrisburg-Syracuse
Harrisburg-Ottawa
Harrisburg-Montreal

Baltimore-Syracuse
Baltimore-Ottawa

Washington DC-Syracuse
Washington DC-Ottawa (capital to capital!)

Plus Scranton to each of those 6 destinations, and Binghamton to each of those 6 origins.

I bet that total of 34 city to city connections* can't be topped**.



*Minimum metro population 250K
**Maximum trip length 750 miles

[Kniwt]

Dual purpose? Airstrip in the middle of YT 5:

[snowc]

Good example: I-81 in Scranton. Carries the Scranton traffic and also the Binghamton NY traffic.

I-81 between Scranton and Binghamton not only qualifies, but blows everything else out of the water.

You've got:

NYC-Toronto
NYC-Buffalo
NYC-Rochester
NYC-Syracuse
NYC-Ottawa

Philadelphia-Toronto
Philadelphia-Buffalo
Philadelphia-Rochester
Philadelphia-Syracuse
Philadelphia-Ottawa

Allentown-Toronto
Allentown-Buffalo
Allentown-Rochester
Allentown-Syracuse
Allentown-Ottawa

Harrisburg-Syracuse
Harrisburg-Ottawa
Harrisburg-Montreal

Baltimore-Syracuse
Baltimore-Ottawa

Washington DC-Syracuse
Washington DC-Ottawa (capital to capital!)

Plus Scranton to each of those 6 destinations, and Binghamton to each of those 6 origins.

I bet that total of 34 city to city connections* can't be topped**.



*Minimum metro population 250K
**Maximum trip length 750 miles

That's a lot of destinations! 

[jeffandnicole]

Wasn't the whole purpose of the interstate system to basically connect cities to each other? So every Highway should have at least a dual purpose if not more.

[webny99]

OK, how about this one:  I-70 between Effingham and Indianapolis.
  Oklahoma City/Albuquerque ↔ Washington/New York
  Dallas/Houston ↔ Detroit/Toronto

I'd replace Washington with Philly. Google seems to prefer I-40>I-81>I-66 for OKC>DC

[sprjus4]

I-26 between Columbia and I-95 serves as a connection to the I-77 corridor.

[sprjus4]

OK, how about this one:  I-70 between Effingham and Indianapolis.
  Oklahoma City/Albuquerque ↔ Washington/New York
  Dallas/Houston ↔ Detroit/Toronto

I'd replace Washington with Philly. Google seems to prefer I-40>I-81>I-66 for OKC>DC

Debatable, the northern route is about the same time and slightly less miles. It's a coin toss as to what route to take.

[SkyPesos]

Good example: I-81 in Scranton. Carries the Scranton traffic and also the Binghamton NY traffic.

I-81 between Scranton and Binghamton not only qualifies, but blows everything else out of the water.

You've got:

NYC-Toronto
NYC-Buffalo
NYC-Rochester
NYC-Syracuse
NYC-Ottawa

Philadelphia-Toronto
Philadelphia-Buffalo
Philadelphia-Rochester
Philadelphia-Syracuse
Philadelphia-Ottawa

Allentown-Toronto
Allentown-Buffalo
Allentown-Rochester
Allentown-Syracuse
Allentown-Ottawa

Harrisburg-Syracuse
Harrisburg-Ottawa
Harrisburg-Montreal

Baltimore-Syracuse
Baltimore-Ottawa

Washington DC-Syracuse
Washington DC-Ottawa (capital to capital!)

Plus Scranton to each of those 6 destinations, and Binghamton to each of those 6 origins.

I bet that total of 34 city to city connections* can't be topped**.



*Minimum metro population 250K
**Maximum trip length 750 miles

Let's see what I-65 between Nashville and Louisville have with both of your criteria, excluding Louisville or Memphis as end points. Distances between 700 and 750 mi labeled. Like I said above, for SW-NE travel on this portion of I-65, it's most useful for Texas to Ohio and parts of the Northeast, but that's beyond the 750 mi limit you have, so no routes to Texas are listed.

Chicago-Atlanta (719)
Chicago-Chattanooga
Chicago-Birmingham
Chicago-Huntsville

Indianapolis-Atlanta
Indianapolis-Chattanooga
Indianapolis-Birmingham
Indianapolis-Huntsville
Indianapolis-Montgomery
Indianapolis-Mobile (734)
Indianapolis-Pensacola (730)

Cincinnati-Little Rock
Cincinnati-Memphis
Cincinnati-Jackson
Cincinnati-Huntsville
Cincinnati-Birmingham
Cincinnati-Montgomery
Cincinnati-Mobile (719)
Cincinnati-Pensacola (715)

Columbus-Little Rock (725)
Columbus-Memphis
Columbus-Huntsville
Columbus-Birmingham
Columbus-Montgomery

Cleveland-Memphis (731)
Cleveland-Huntsville
Cleveland-Birmingham (712)

Dayton-Memphis
Dayton-Little Rock
Dayton-Jackson
Dayton-Huntsville
Dayton-Birmingham
Dayton-Montgomery

Fort Wayne-Chattanooga
Fort Wayne-Birmingham
Fort Wayne-Huntsville
Fort Wayne-Montgomery
Fort Wayne-Atlanta

Grand Rapids-Birmingham (737)
Grand Rapids-Huntsville
Grand Rapids-Chattanooga

Lansing-Birmingham (729)
Lansing-Huntsville
Lansing-Chattanooga

Toledo-Birmingham
Toledo-Huntsville
Toledo-Memphis

Detroit-Birmingham (726)
Detroit-Huntsville
Detroit-Memphis (744)

Pittsburgh-Huntsville

Erie-Huntsville (728)

Milwaukee-Huntsville
Milwaukee-Chattanooga

That's 54 I counted so far, and I might be missing some since 250k metro population isn't that much. Think some other interstates, like I-57, can get that much too.

Now including Louisville or Nashville as endpoints to any city not listed above already because of the 750 mi distance limit

Louisville-Shreveport (730)
Louisville-New Orleans (707)
Louisville-Savannah (668)
Louisville-Tallahassee (664)

Nashville-Green Bay (682)
Nashville-Buffalo (704)
Nashville-Hamilton (723)
Nashville-Mississauga/Toronto (750)*
*Nashville to Toronto is 763 miles, but since Mississauga is part of the GTA and makes the 750 mile limit, I'm counting it

[achilles765]

I'll make an attempt at this

IH 45 is both the major connection between the two largest and most important cities in Texas as well serving as a connection to places like Tulsa and farther north.

IH 10 connects the major petrochemical cities of Houston and Beaumont (not a major city but very important industrially) to the industrial sector in lake Charles as well as to the rest of the gulf coast) and also is the major coast to coast route for the southern us.

[cwf1701]

I-69/I-94 in Port Huron carries Detroit-Toronto (as a bypass of Windsor), Chicago-Toronto (and all points west), and Indianapolis-Toronto (and all points south). it also connects cities like London ON, Lansing MI, Flint MI, Grand Rapids MI, etc.

[hobsini2]

One could make a case for I-39 especially between I-74 and I-43.
Chicago & East/Southeast - Minneapolis & Northwest
St Louis & South - Minneapolis & North
St Louis & South- Milwaukee & North
Quad Cities/Des Moines & West - Milwaukee & North

[ftballfan]

The Ohio Turnpike between Toledo and Cleveland:
Chicago and most areas north of a line from Portland (OR) to Chicago - the entire Northeast Corridor
Denver/SLC/San Francisco Bay Area - Boston and upstate New York

[TXtoNJ]

I'll make an attempt at this

IH 45 is both the major connection between the two largest and most important cities in Texas as well serving as a connection to places like Tulsa and farther north.

IH 10 connects the major petrochemical cities of Houston and Beaumont (not a major city but very important industrially) to the industrial sector in lake Charles as well as to the rest of the gulf coast) and also is the major coast to coast route for the southern us.

Eh, I think the best Houston-area example is I-10 west serving both San Antonio and Austin, even though 290 is the designated route to the latter.

I-70 in the Rockies was specifically constructed to serve both intrastate traffic into the mountains, and Los Angeles to Chicago truck traffic (along with being a much needed relief route to I-80 in Wyoming).

[debragga]

The I-20/I-59 concurrency in Mississippi and Alabama serves Dallas-Atlanta and New Orleans-Nashville traffic, along with many other city pairings that someone can list out if they wish.

[sparker]

I'll be Captain Obvious here -- I-15 between the Ontario (CA) area and Barstow serves traffic from Los Angeles to (a) Flagstaff, Albuquerque, OKC, etc. via I-40, (b) the Rocky Mountain recreational zone, Denver, KC, Omaha, and even Chicago via I-70, 76, 80, etc.. and (c) the Wasatch Front (Provo, SLC, etc.) as well as Yellowstone Park, the latter via US 20. 

I would also say that the functional equivalent on the East Coast is I-78: from NYC and the NJ port area, it funnels traffic (via its I-81 extension through greater Harrisburg, PA) to I-76 and thus westward to I-70 and most of the remainder of the nation.  It also accesses much of the South by remaining on that same I-81 extension toward Knoxville, TN, where it further disperses to Nashville/Memphis/Little Rock/Dallas or down I-75 to Chattanooga, where an additional dispersal takes place via either I-75 or I-24/59.  But much of the traffic -- in either direction -- either begins or ends up somewhere along or close to I-78.