Be alert for speed trap at Estilline
Charles Goodnight home and museum, Goodnight, TX
Coyote Bluff, Tacos Garcia, Tylers BBQ, Blue Sky for lunch in Amarillo. Not much else to eat until Russel's
Palo Duro Canyon is worth a full day
Russel's Truck Stop just across border into NM, great antique car museum. Free, donation to charity requested. Nice stop with lots of junk food/snack selections. Has a restaurant, I have n idea if it's any good.
If you're into Route 66, take it through Tucumcari. Best preserved 1950s to 1970s Route 66 out there. A couple of good restaurants there, such as Kix and Dels.
In Santa Rosa, the new Pilot on Route 66 (exit 277 and go north then west) is the best stop. The Blue Hole is interesting and a quick stop. Couple of good restaurants there, too. More Route 66 sights.
Clines Corners is an 80 year old tourist trap. We avoid it. Turn there to the most direct route to Santa Fe. Though you can take highway 84 for different scenery. We also like highway 3 that goes through Villanueva State Park. Highway 3 is narrow, not well maintained and twisty. 84 or 285 are both good.
Off 285, the old railway station at Lamy is well preserved and still in use. See it if you're into Manhattan Project history.
In Santa Fe, we love Gabriel's Mexican food off 285 north of town. Also drove out to Chimayo last trip out, to Ranchos de Chimayo. Very good.
Los Alamos has two great museums, the county history museum and the Bradbury Science Museum. Lots of nuclear/Manhattan info at both. There's a walking tour of some of the Manhattan Project sites. Also, they are starting a Manhattan Project Museum, and there will soon be bus tours onto the LA lab to see the WWII sites. Spectacular trails on the mesa edge. And, of course, Bandalier is a great tour.
Valles Caldera is the most spectacular place you can go. Drive up the road through LANL to Valles. Some great hikes past there, and we enjoy the Gilman Tunnels near Jemez.
Let me know if you want more Los Alamos info.