(NEXSTAR) – Few California park experiences are more relaxing than sitting in a tiny rustic cabin above Stinson Beach and watching the whales and porpoises glide by. But the process of booking one of 10 reservations at the Steep Ravine Cabins is perhaps the most anxiety-inducing park experience this side of Yosemite rock climbing.

If you don’t beat out other campers and claim your rental in the first five seconds of the booking window, you have to hope you get lucky on a rare cancellation. 

Sunset from a Steep Ravine cabin (Credit: Bill Disbrow/Nexstar)

Steep Ravine in Marin County is one of the toughest bookings in the entire California State Parks system. In fact, many of the most in-demand “camping” accommodations aren’t tent sites or RV hookups, but cabins and cottages the park system makes available for rental. 

We wanted to know which sites are most brutal to reserve, and we put the question to state park officials. The rooms at the five locations below are the most heavily booked solid in the state parks system this summer, counting the peak season from May 1 to Aug. 31. 

The historic cottages at Crystal Cove State Park – This popular Orange County gem offers tidepool exploration and sandy beaches all with proximity to dozens of rustic cabins dating back to the ’30s and ’40s. The area is considered a historic district, and the charming cabins range in size from accommodations for two to large “hostel-style dormitories,” according to the parks system

City Hotel at Columbia State Historic Park – This park off of Highway 49 southeast of Sacramento offers a glimpse of Gold Rush living in a small town setting. You don’t have to book a reservation or even pay an entry fee to stroll the streets and get a 19th-century vibe, but an evening in your parlor at the City Hotel will have you ready to grab your pan and set off to strike it rich. 

Jedediah Smith Redwoods State Park cabins – This facility near the Oregon border offers a launching-off point to explore the rugged and breathtaking Smith River, touted by park officials as “the longest major free-flowing river in California.” It also hosts just four cabins, making the rentals tough to come by. Units accommodate up to four people inside and up to two more in a tent outside, according to California State Parks. 

Steep Ravine Cabins at Mount Tamalpais State Park – A short drive north from San Francisco sits this 10-cabin rustic facility overlooking the Pacific coast. From here you can enjoy a quiet nearby beach or climb the seven miles to the top of Mt. Tam to take in views of San Francisco and the surrounding Bay Area.

Cabin at Pfeiffer Big Sur State Park – This park is better known as a prime camping destination in Big Sur with 189 available tent and RV sites. But Pfeiffer does have one lone cabin, available with an adjoining campsite that will allow up to six total guests. At just $75 a night, it’s no wonder this spot is difficult to secure. 

If car or tent camping is more your speed, check out our list of California campgrounds that are the most heavily booked for peak season.