Sierra National Forest - Mammoth Pool cancellation alerts - get notified when a site opens

Mammoth Pool is a 4-site campground in Sierra National Forest, reservable through the Recreation.gov reservation service. Reservable options here include tent, rv and trailer. Recreation.gov describes it this way: Mammoth Pool will be closed until further notice due to a massive hazard tree removal. Mammoth Pool Campground is located half a mile from the recreation area at Mammoth Pool Reservoir. Popular Recreation.gov campgrounds like this one book up quickly. Reservations open on a rolling window, commonly up to six months before arrival, and the best summer weekends are often fully reserved within minutes of that window opening. Once a date fills, the reservation system shows no availability at all, and from then on the usual way to get one of these 4 sites is a cancellation. When a booked party changes plans, their site is released back into the system and briefly becomes available again, frequently at odd hours and often taken within minutes by whoever happens to be looking. grabio watches Mammoth Pool on a fixed one-minute schedule and compares what is available now against the previous check. The moment a site matching your dates opens, whether from a same-day cancellation or a newly released block of inventory, it alerts you so you can book it yourself on the official Recreation.gov system. It never books, holds, or reserves anything for you; it only tells you the instant a spot appears, so you are not left refreshing the reservation page by hand. Alerts arrive by email by default, with an optional Telegram ping, and you can watch a specific set of dates or a flexible window, so you only hear about openings that fit the trip you are actually planning. Because grabio only reads the public reservation system, it sees exactly what Recreation.gov shows, and it keeps watching until a matching site opens or your dates pass. Exact nightly fees, the site map, and the current booking window are on the official Recreation.gov page for Mammoth Pool.