RAY CHAVEZ/Staff photos

Don Hart, above, of Walnut Creek has been setting up a lighted holiday railroad-and-village diorama in his Buena Vista neighborhood home for more than 20 years. "It started as a handful of little houses on the piano, and it gets bigger every year," said Hart, whose display now includes an HO-scale model train. It takes about three weeks to set up, he said, and sometimes stays up into February. "It takes so long to put it up, I don't really want to take it down," he said. Though it isn't open for formal viewing, he said, many friends and neighbors who come by the house each holiday season get to see it.