Correction: Neither the Grand Canyon nor Meteor Crater is in Winslow, Arizona.
Grand Canyon (South Rim): Northern Arizona, ~95 km north of Williams/I-40. Meteor Crater (Barringer Crater): Eastern Arizona, ~60 km east of Flagstaff, ~10 km south of I-40 (exit 233). Winslow: On I-40, ~50 km east of Meteor Crater turnoff.
Grand Canyon Village → Meteor Crater: ~275 miles (440 km), ~4 hours via US-180 W → I-40 E. Scenic: San Francisco Peaks, Flagstaff, high desert.
Doable in a long day (dawn at Grand Canyon, midday at Crater, sunset back) but rushed. Better: overnight in Flagstaff/Williams—explore both properly. Meteor Crater (privately owned): 1.2 km wide, 170m deep, 50,000 years old. Grand Canyon: Needs no introduction.
Winslow is a Route 66 stop (Standin' on the Corner park)—not a gateway to either attraction.