An adobe house with a tiled roof and palm-trunk beams, looking just as it did at the end of the 18th century: study, dining room, parlor, bedroom and oratory, all furnished with period pieces. This is where the leaders of independence met in secret. Beside the house runs the Callejón Histórico, the narrow passage the patriots slipped out through that night. It's a small, intimate and beautifully preserved museum — one of the few surviving examples of colonial architecture downtown.

It was built in 1772 by the Spaniard Antonio Martínez Sáenz. On the night of May 14, 1811, a group led by Pedro Juan Caballero left through the adjoining alley toward the barracks; at dawn on the 15th, Governor Bernardo de Velasco relinquished power. The State bought the house in 1943, it was declared a National Historic Monument in 1961, and it opened as a museum on May 14, 1965.