Dating from 1749, the colonial Cabildo stood on Mendoza’s Plaza Mayor until 1861, but that year’s devastating earthquake made authorities rebuild the city center at present-day Plaza Independencia.

Renamed Plaza Pedro de Castillo, the plaza now holds the Museo del Area Fundacional, a spacious modern structure that shelters the excavated foundations of the adobe Cabildo (and the subsequent slaughterhouse).

As a museum, it’s a thoughtful account of Mendoza’s development since pre-Columbian times, with ethnographic, historical, and contemporary detail. Its strengths are Huarpe Indian artifacts as well as historical dioramas and photographs; loaner booklets with English descriptions of the exhibits are available. There’s a pleasant café and a souvenir shop.

As an archaeological site, its strength is the subterranean remains of the fountain where 19th-century Mendocinos came to collect potable water brought from the Andes by an underground aqueduct. Guided tours of the site cost an additional US$0.50.

The Museo del Area Fundacional (Alberdi 571, tel. 0261/425-6927, US$1.50 adults, free Wed.) is open 8:30 a.m.–8 p.m. Tuesday–Saturday and 3–8 p.m. Sunday.