In the wake of recent high-profile home robberies wherein thieves managed to abscond with millions of dollars worth of art and goods, owners have embraced the newest trend in luxury homes: security. Curbed recently profiled a $12 million 9,800-square-foot mansion in Hillsborough, California mansion. The five bedroom, seven bathroom estate was originally built for banking heiress Celia Tobin Clark, and features fitting security, including a vault with foot-thick steel doors. The current owner is art dealer Andre Ruzhnikov, who specializes in the sale of Russian art and objets d’art.

For the full listing and more photos, please visit Curbed.