As a kid growing up in the Santa Monica Mountains I visited Castro Peak many times. When I first hiked up the summit on May 27, 1973 it was a beautiful summit with a stand of pine trees and an abandoned fire lookout tower. The tower was open and still contained some rainfall records from the final years of operation.
Over the years a communications site was established and expanded. There was even a local FM radio station, KBU (‘BU as in MaliBU) as I recall. It all burned in the Dayton Canyon Fire on October 9, 1982 – a fire that nearly destroyed my family’s home. I listened to KBU go off the air that day as we fought the fire.
I know that the Los Angeles County Sheriffs Department has a facility there now.
I was surprised to see that Castro Peak has never been activated. This morning I explored a few different possible routes and was met with resounding failure. Everywhere I looked I found a lot of NO TRESPASSING/PRIVATE PROPERTY signs.
Mystery of why Castro Peak has never been activated solved.
I might ask a few friends who work with the Lost Hills Sheriff’s Department if permission might be granted, but I’m not holding out a lot of hope.
Ah for the good old days!

More information about why Castro Peak is closed.