Once a year at the holidays, the California State Parks and the Old Monterey Preservation Society open the doors to about 20 historic adobe homes and buildings clustered in a five-block area of Monterey, Calif., on the California coast, two hours south of San Francisco. Visitors lead themselves on self-guided tours of the 19th-century structures, each of which is staffed with docents dressed in period costume, who inform visitors about the former occupants of the homes and the historic events that took place there — such as the signing of the California State Constitution in Colton Hall in 1849. The interiors are festooned with holiday decorations and the exteriors lit by candlelight, and there's lots of live music, ranging from a Jalisco harp player at Casa Soberanes to bagpipers at the Stevenson House. Christmas in the Adobes is scheduled on December 11 and 13, from 5 p.m. to 9 p.m. Tickets cost $20 for adults, and $2 for children aged 17 and younger. For more information call 831-649-7119.