Gulley built the 8,000-square-foot (743-square-meter) castle over the course of 15 years out of unusual and inexpensive materials. Parts of the castle remain unfinished, but it does contain a chapel, a cantina, a barbecue pit, a wishing well, 13 fireplaces, and a dungeon. He utilized unusual materials, such as car parts, salvaged railroad tracks, statues, and traditional southwestern adobe, throughout the three stories and 18 rooms.
In 1945, Boyce died and left the house to his teenage daughter, Mary Lou, and her mother. They both moved in shortly after, and Mary Lou stayed until her death in 2010.
The castle has a good number of stairs and so is not wheelchair accessible.
Tours operate throughout the day; reservations are not necessary.
Children under 5 are admitted free of charge.
Originally built in a secluded location, the castle is now easily reached by taking 7th Street South to Mineral Road and then heading east to the Mystery Castle entrance.
The castle is open from October through May; it is closed during the hottest months of the summer. First thing in the morning or later in the afternoon are the coolest times in the desert and the most pleasant to visit.
The times that Boyce and Mary Lou spent building sandcastles on the coast of Seattle inspired the idea for the castle. Mary Lou would be so upset when the ocean waves came and washed her sandcastles away, and she suggested to her father that he should build a castle in the desert where no water could ruin it. The idea for the mystery castle was born.
