The drive from Nageezi to Chaco's visitor centre is 33 km, of which the last 21 km are unpaved County Road 7900 — corrugated, often deeply rutted, and notorious among rental-car companies. In dry weather it takes a careful hour in any vehicle with reasonable ground clearance. After heavy rain or in winter it can be impassable for days, and the National Park Service publishes road conditions on the park website. Check before you commit.
Coming from the south on US-550 is the official recommended route. Do not be tempted by the shorter-looking dirt approach from Highway 57 to the south — it is rougher again and crosses unsigned washes.
The nearest airports are Farmington (FMN) about an hour to the north and Albuquerque (ABQ) three hours south. There is no public transport to the park; a rental car is essential. Fuel up before the turn-off, as there is none at Nageezi and none inside the park.