The minimum land requirement for a Hipcamp site is generally just two acres. Some listings look like ordinary suburban back yards, but there are also off-grid plots, Airstreams, and tree houses. In Northern California, booking a public campsite is a blood sport. The Bay Area overflows with young people who have R.E.I. Co-op memberships and drawers full of sweat-wicking apparel—people who spend Friday and Sunday nights packing and unpacking their Subarus, who own cat-hole trowels, who love to live here because it’s easy to leave in pursuit of the sublime. From Big Sur to Mendocino, many public campgrounds are booked months in advance; Yosemite is a lost cause. It’s common practice to wake at five in the morning to hover over a computer, poised to nab a site as soon as it becomes available. This is both a regional issue and not. Across the country, America’s national parks are overcrowded and overbooked. The reservation system is riddled with bots. A cottage industry of apps and services has emerged to monitor campsite availability and, in some cases, provide alternatives. Around 2016, I began to notice that friends were passing around listings from Hipcamp, a platform for campsit...