USA Guide
The Rockies
Mesa Verde National Park
The only national park in the US devoted exclusively to archeological remains, Mesa Verde National Park is so far off the beaten path that its extensive Ancestral Puebloan ruins were not fully explored until 1888, when a local rancher discovered them on his land.
The access road climbs south from US-160. Once past the entrance station ($15 in summer, $10 rest of year, good for one week), the road climbs and twists for fifteen miles to the Far View Visitor Center (late April– mid-Oct daily 8am–5pm; 
970/529-4465). Immediately beyond, the road forks south to the two main constellations of remains: Chapin Mesa and Wetherill Mesa. To tour any of the major ruins, you must buy timed tickets ($3; purchase at Far View in summer, Chapin Mesa Archeological Museum rest of year).
Beyond the museum, Ruins Road (daily April– early Nov, 8am– dusk) consists of two one-way, six-mile loops. If you're pressed for time, follow the eastern one to reach Cliff Palace, the largest surviving Ancestral Puebloan cliff dwelling anywhere. Tucked one hundred feet below an overhanging ledge of pale rock, its 217 rooms once housed over two hundred people.
Balcony House, a little further on, is clearly geared towards defense; access is very difficult, and it's not visible from above. Guided tours involve scrambling up three hair-raising ladders and crawling through a narrow tunnel, teetering above a steep drop into Soda Canyon.
At the end of the twisting twelve-mile drive onto Wetherill Mesa (daily late May to early Sept 8am–4.30pm; no RVs), you can catch a free miniature train to the Long House, the park's second largest ruin, set in its largest cave. Hour-long tours descend sixty or so steps to reach its central plaza, then scramble around its 150 rooms.