Want a July 4 campsite at Big Sur, Leo Carrillo or Crystal Cove? Get up early on Jan. 4

Yes, it’s still winter. But if you’re harboring thoughts of camping on July 4 — or any time in July — now is the time to start booking at some of California’s most popular campgrounds.

California state parks use a reservation system that opens up six months ahead of your intended stay. So if you want to book a campsite for July 4, the window of opportunity opens on Jan. 4 at 8 a.m.

And with the nationwide surge of interest in camping and other outdoor activities since the pandemic, the urgency may be even greater than usual this year.

The key to state park reservations is Reserve California, the online booking system that handles about 15,000 campsites in state parks throughout California. You can also book your campsite by phone at (800) 444-7275 (8 a.m. to 6 p.m.).

Among the state’s most popular campgrounds: Pfeiffer Big Sur State Park, which has about 190 spots for tents, trailers and RVs; South Carlsbad State Beach and Leo Carrillo State Park in Malibu. (One risk with a Big Sur booking: The most direct route from Los Angeles in Highway 1, which is vulnerable to closure by landslides. Be sure to check highway status on the Caltrans website before any driving trip to Big Sur.)

For national parks in California, including Yosemite and Joshua Tree, bookings are made through Recreation.gov. As the website notes, “reservable campsites are available up to five months in advance on the 15th of each month at 7 a.m. (PST). For example, on Jan. 15, arrival dates from May 15 to June 14 become available to reserve, and therefore, the full potential arrival window would be from Jan. 16 to June 14.”

In California’s state parks, campers are typically allowed to modify reservations up to two times. The exception is Crystal Cove State Park in Orange County, where modifications are forbidden. (Demand for Crystal Cove’s seaside cottages is extremely high.)

At most state campgrounds, online reservations are accepted as late as two days ahead of arrival. But at the most popular destinations, state and federal, all campsites get grabbed in the first weeks, or days, or sometimes hours, of availability.

At Yosemite, Recreation.gov warns, campsites “typically sell out in minutes.” To be competitive, log in to your account (or create an account) before the 7 a.m. opening of sales.