Contra Costa County is a county located in the state of California, United States. It is situated in the East Bay region of the San Francisco Bay Area and covers an area of approximately 720 square miles. The county has a population of around 1.15 million people, making it one of the largest counties in the state.

The Padre Picnic Area is a popular spot within Tilden Regional Park, located near Orinda, California. This picnic area is well-suited for group gatherings, offering amenities that cater to various outdoor activities.

The Redwood Valley Railway is a miniature railroad located in Tilden Regional Park, near Orinda, California. The railway was founded in 1953 and is run by a non-profit organization of volunteers.

One of the District's three oldest parks, Tilden has been called the jewel of the system, and its recreational activities have become a happy tradition for generations of East Bay youngsters. From a carousel ride and a picnic to a swim at Lake Anza and a stroll through the Botanic Garden, Tilden has variety to delight everyone.