Are there any marathons in the US whose courses lie in three or more states? I know they run the Shiprock Marathon near Four Corners, but I don’t think that one even crosses one state line.
For that matter is there any possible course other than near Four Corners for which four (or more) states would be involved in its 26+ mile course?
(No running in place on airplanes, etc. especially not if they are on treadmills.)
Starting in VA and ending in PA, crossing WV and MD at their narrow parts. Others are probably possible.
NJ, DE, MD, PA is also possible.
This race is 20 miles, not a marathon, but it runs through Massachusetts, NH, and Maine. Most major marathons are in cities, which tend to not be right on the border. Plus, I looked through wiki’s list of marathons and none were multistate. You would probably need to look into ultramarathons to start crossing state lines.
And there is/was the Niagara Falls International Marathon that started in New York State around Buffalo, crossed into Canada, and finished near the Canadian/US Niagara Falls. Nice flat course, I ran it many hears ago.
I was just thinking about a related question a few days ago. I think the shortest route that connects 5 states is from the NH-VT-MA tripoint to the RI-MA-CT tripoint. That’s almost 60 miles as the crow flies. From the TX-OK-NM tripoint to the KS-CO-OK tripoint is only a little farther.
Anther short distance similar trip would be IL KY MO tripoint to TN AR MO. Thoug it might even be shorter not to go to the tripoint but to go to the TN northern border and then hop across the MO boot heel.
The SC NC GA tripoint to Ga AL TN tripoint is also pretty short.
There is a marathon in El Paso, TX every year that runs along the border fence with Mexico for a ways. It’s nice to have people cheering from another country! I think it would be pretty neat if the race crossed into Mexico and back, but I suppose there would be some logistics to consider with that one.
Don’t people do that every day?
There used to be a race that ran from Elkhart, Kansas to Texoma, Texas. I believe it was called Run Accross Oklahoma or something similar. It was mostly done as a relay race, but every year a few individuals ran it as an Ultra. I took part in it twice and it was, for the most part, great fun. All of your team (except the runner of course) would pile into a van or an RV and drink beer (or whatever) until it was your turn to run. The length of the relay legs were pretty much up to the competitors. I don’t know if the race is still done. There were no established water or aid stops. You pretty much took care of your own.
To make it a four state deal, one could move the four or five miles west of Elkhart and include a bit of Colorado.
Similarly, the Detroit Free Press marathon extends into Canada, traveling both through the Windsor Tunnel and across the Ambassador Bridge.
Somebody trying to be really efficient on that “marathon in every state” life goal? 
From Mexico, sure, but not the “into” part. (If the return part is the same day, it’s probably in an ICE wagon rather than on foot.)
As a lark over lunch time I constructed a set of marathons to include every state. I got down to 20 (including AK and HI but excluding DC). The races are:
ME-NH
CT-RI-MA
VT-NY
NJ-DE
VA-WV-MD-PA (This is mostly to get another four-state marathon. It looks pretty rugged and combining NJ-DE-PA might be more practical.)
NC-SC-GA
FL-AL
OH-IN-MI
IL-WI-IA
KY-TN-MO (I hope you don’t need to swim the Mississippi here)
MI-AR-LA (ditto)
MN-ND-SD
NE-KS
OK-TX
CO-UT-AZ-NM
WY-MT --------- (ID-WY-MT
ID-OR-WA ------ OR-WA might be more practical)
NV-CA
AK
HI
Can anyone do any better? Obviously DC can be included as a 21 or combined with MD and/or VA with some reshuffling, but I couldn’t get it to 20 including DC.
I’m also not positive if there are bridges near enough the tri-points of KY-TN-MO and MI-AR-LA to make those actually feasible marathons.
Actually using PA-NJ-DE and WV-VA-MD, you can do it all as a series of 10K, 1 mi, or even 100 yard dashes except possibly for finding bridges – a lot less work.
I had NJ-DE-MD-PA pegged as a 4 state - start just inside NJ, take the bridge over the Delaware river, if feasible, cross DE into MD, hang a hard right, go north into PA (or cross DE in PA, go south into MD).
Looks like simply following US 522 would suffice. If by “rugged”, you mean it would have some steep hills, I suspect you are right.
I’m pretty sure that is a valid four-stater as mentioned earlier in this thread, but it doesn’t save any on finding all 50 states in fewest.