How long is Route 66?

Plan on doing less than 200 miles per driving day. Ideally, stay below 150 miles unless you're in the Mohave desert.
Are you sure you're not asking how long it would take to drive Route 66?
If so, please read up on how long it takes to drive Route 66i, as in the case of Route 66 you need far more time than the distance would suggest.
It's complex
The length of Route 66 for those interested in the academic number is more complicated than just a single number.
First of all: different sources will give you different numbers.
There are reasons why not all but one of these numbers are wrong:
- Route 66 underwent many changes throughout its life
as a commissioned highway. Even the endpoints moved (e.g.,
in 1936 Route 66 got extended from downtown Los Angeles
to Santa Monica).
Additionally, Route 66 got realigned a lot. This results in shorter lengths as loops such as the Santa Fe loop that was cut off, or in longer distances as cities got bypassed to draw traffic out of and around city centers. - There was more than one version of Route 66 at the same time in some places. You have detours, bypass, alt, truck, and city alignments through or around cities like Saint Louis. Consequently, not all of them had the same length.
- The exact number of miles was never really that important back in the day, even if a proper surveil was done, no car or truck odometer was accurate enough for the rest of the population to care in great detail. As a matter of fact: our modern car odometers still aren’t up to the task of measuring distances with high accuracy over long stretches.
In the end, to even get to a single number, the least we need is a date on which to focus. And we need to allow a reasonable margin of error in that number at the same time.
What we have done is used measurements made by Stefan Joppich based on his research on where Route 66 ran throughout the years and added up the amounts per state for three different years:
State | 1926 | 1939 | 1947 |
---|---|---|---|
Illinois | 301 mi | 287 mi | 284 mi |
Missouri | 317 mi | 321 mi | 316 mi |
Kansas | 13 mi | 13 mi | 13 mi |
Oklahoma | 432 mi | 397 mi | 404 mi |
Texas | 186 mi | 175 mi | 175 mi |
New Mexico | 487 mi | 380 mi | 379 mi |
Arizona | 401 mi | 406 mi | 395 mi |
California | 314 mi | 326 mi | 314 mi |
Total | 2448 mi | 2304 mi | 2278 mi |
You cannot drive any of these alignments anymore. All of them have missing sections, have been cut up by missing bridges, interstates, etc. requiring you to mix and match between the different alignments and even some connecting roads to make your pilgrimage on Route 66 today. In the end: you'll drive a much longer distance if you try to cover it all.
The number of 2448 miles (about 3940 km) is the easiest to get people to rally behind. Additionally, it matches up with surveils done in the 1920s.