Two oak trees on a long dirt road with the rolling hills alongside. This was all one would see early in 1950 when A.E. Hanson (who also developed the community of Rolling Hills on the Palos Verdes peninsula) began his development of Hidden Hills.

In 1950, a large sign on Ventura Boulevard at the intersection of Long Valley Road announced:

1000 Acres of Elbow Room
Live in
HIDDEN HILLS
Where Living Is Fun!
Full Acre Lots $4750

The "1000 acres" were composed of the following purchases: 1) in 1949, 700 acres acquired from E.E. Hurlbutt; 2) in 1950, 160 acres purchased from Nace, et al; 20 acres from Mrs. Lasher; 119 acres from the Straubinger family; and 5.6 acres from Spinks — a total of 1004.6 acres.

Two model homes were built in 1950 — 23704 Long Valley Road and 23629 Long Valley Road. The latter was the first house purchased. Leo Gorcy, one of the Dead End Kids of movie fame, bought it for $35,000.

Ever wonder where the street names came from? Long Valley and Round Meadow because that's what they looked like — a long valley which turned into a round meadow. Lasher Road was named because the Lasher home was on that road. One field was covered with six-foot-high mustard and was a gathering place for red-winged blackbirds, thus Wingfield Road. According to A.E. Hanson, his children read books about early Western American explorers and trappers, so the roads in the Round Meadow area were named for these trailblazers, in hopes that future generations of children in Hidden Hills would become interested in the history of the American West from 1805 to 1830.

Lamond Chamberlain became the second major developer of Hidden Hills in 1956. A.E. Hanson turned over his declarant's rights and his fee ownership of certain properties to the Hidden Hills Community Association, including the pool property on Long Valley, the bus stop property at Jed Smith and Round Meadow, Long Valley Road itself, and the front gate house. He then sold his undeveloped land to Hidden Hills Estates, Inc., Lamond Chamberlain being the president and Ruby Chamberlain the secretary.

By 1957, the cost of a three- or four-bedroom home on a one-acre site was $27,500 – $47,500. One- to five-acre homesites were selling for $7,950 – $12,500.

In October of 1958, Alice Stelle and Eleanor DeCarteret started a monthly newspaper, the "Las Virgenes Enterprise." In 1963, it started weekly publication. Alice and Eleanor later sold the paper, but it is still published today.

In the summer of 1959, six-year-old Deborah Williams said, "Wouldn't it be fun if we could sit on our ponies and horses for church?" and thus originated the "Church on Horseback." It was truly an outdoor devotional worship service, and was a wonderful experience for those of all ages who loved the great outdoors and horses. Families arrived not only on ponies and horses, but also on donkeys, in buggies, and in surreys — yes, with the fringe on top.

In the spring of 1961, civic leaders in the tiny community of Hidden Hills launched a drive to form a city. They were faced with the prospect of being annexed to the City of Los Angeles and having Burbank Boulevard extended through the community. The petition for cityhood was signed by 79% of the voters, and in spite of the fact that the Los Angeles City Council's Planning Committee opposed the incorporation, it was approved by the Board of Supervisors. September 19, 1961 was designated as election day, when a total of 358 votes were cast for incorporation (83% of registered voters), with 71 votes against. The area of the new city was approximately 1.3 square miles, with a population of a little over 1,000 and an assessed valuation of $2,681,910. On October 19, 1961, Hidden Hills became the 73rd city in the County.