Castaic Lake, the largest lake in Los Angeles County, is the ultimate summer escape just a 30-40 minute drive from DTLA. It’s not too soon to start planning a visit, because Castaic Lake’s recreational swim area will be open before we know it.
The Lower Lake usually opens for swimming on Memorial Day, which this year falls on May 25, 2026. Attractions include the massive Cali Splash inflatable water park, boat rentals, and more quintessential summer activities. Pack your sunscreen, prepare a picnic, and keep reading for everything to know before you hit the road.
Swimming at Castaic Lake
Swimming is only permitted at the Lower Lake’s designated Swim Beach when lifeguards are present. There is no entry fee to enjoy Swim Beach.
🗓️ Opening hours and dates: The swim area generally opens from 10 a.m. – 6 p.m. on weekends starting Memorial Day, and then daily from June through Labor Day.
Cali Splash Park
One of Castaic Lake’s most popular attractions is Cali Splash Park, which also opens for the season around Memorial Day. This is SoCal’s largest inflatable aquapark, which comprises 45 epic floating obstacles and features.
Sessions are available every 2 hours with a 2-hour duration, or you can also purchase a full day or full season pass. Kids over 9 may participate alone, but an adult must accompany kids from 4-8 years old.
🗓️ Opening hours and dates: Cali Splash Park opens on Saturday, May 23rd, 2026. Visitors can enjoy it from 10 a.m. – 6 p.m. Wednesday through Sunday until September 28th, 2025.
More summer activities at Castaic Lake
The Castaic Lake State Recreation Area includes both an Upper Lake and a Lower Lake lagoon with 29 total miles of shoreline.
The Upper Lake is designated for power boating, jet skiing, wakeboarding, and sailing, and the Lower Lake is reserved for non-motorized activities like kayaking, canoeing, and paddleboarding.
Both lakes offer great fishing and are known for record-breaking bass, trout, and catfish. Some popular fishing areas are the lagoon’s fishing pier and the Upper Lake’s east arm.
You can also enjoy over 7 miles of trails for hiking and cycling, tent and RV camping with on-site amenities, and picnic areas.
Note that Castaic Lake SRA is one of the few California State Parks that does not accept the Annual State Parks Pass.
🌐 Learn more:
