The neighborhood of Holmby Hills is a part of the district of Westwood. Along with Bel Air and Beverly Hills, it forms the Platinum Triangle - a section of affluent areas in Los Angeles County.  Homes in this community are known for their large lot size, long driveways and privacy hedges.

Arthuer Letts, founder of world-renowned Broadway and Bullocks Department Stores, owned approximately 3,300 acres of the Wolfskill Ranch which formed the foothills of Sunset Blvd all the way to Pico Blvd. His son-in-law, Harold Janss, and owner of Janss Investment Company began developing the area known today as Westwood. In 1925, Janss Investment sold approximately 400 acres of this land to the City of Los Angeles. Some of the land was donated to the State of California allowing them to build what is now the UCLA campus. Today, Westwood is a vibrant community of fine dining, shopping and a place to experience the arts.

A well-known street in Holmby Hills is South Mapleton Drive which lies between Beverly Glen Blvd and the Los Angeles Country Club.  Some residents of Holmby Hills include Hugh Hefner (The Playboy Mansion), Ellen Degeneres, P. Diddy and Petra Ecclestone.