Well, the Route (66) doesn't officially exist anymore. And many segments of the old highway are in serious disrepair and/or are inaccessible (i.e., on private land that the states have surrendered to ROW).

But I agree. One can approximate that route with modern highways and see some interesting remnants of a bygone era.

I disagree with the poster who dissed Holbrook and Winslow. Both towns do have some interesting - if at times quirky - attractions. Petrified Forest National Park (East of Holbrook) features some classic southwestern landscapes. Holbrook has one of the few remaining incarnations of the Wigwam Motel and some life-sized dinosaur re-creations, not to mention what I believe is the only thoroughfare in the U.S. named "Bucket of Blood Street". Winslow has both the Standin' on the Corner Park (for Eagles fans) and the beautifully restored La Posada Hotel. West of Winslow, there are two ghost towns located at the Two Guns exit. The ruins of Two Guns itself are just south of the exit. About a mile north (on a rough dirt road) are the ruins of Canyon Diablo, a boom and bust old West town that is famed for being one of the roughest towns to ever exist in N. America. (The first town marshall was killed within an hour of being sworn in.)

Regarding the suggested Gallup - NM/AZ 264 detour. There's currently some major construction work on AZ 264 between Window Rock and Ganado. Expect delays. If you choose this route, check out the Navajo Nation Museum in Window Rock and Hubbell Trading Post in Ganado. The burger in Second Mesa isn't bad, but beware that if you miss that place there's very little in the way of food, gasoline, bathrooms, etc. until Moenkopi. Just past Tuba City, the "Dinosaur Tracks" are a fascinating ad hoc roadside attraction. Locals sell arts & crafts there and are willing (even eager!) to take one on an impromptu tour pointing out the various dinosaur tracks. Or one can explore them on ones own. Once in Cameron, might as well drive through the South Rim of the G.C. as well before rejoining I-40 in Williams.