Sold out? What to do next

Popular dates at New England's big campgrounds can go within minutes of opening. Missing the release isn't the end: people cancel, and those sites go back on the booking system one at a time.

1. Set a cancellation alert

Start with Campflare, which is free and sends email or text alerts when a site opens up. If you want more frequent scans and text alerts, Campnab is a paid option.

For Cadillac Summit Road, use Recreation.gov's own free "Set Availability Alert" on the reservation page.

2. Watch the second release

Cadillac Summit Road keeps 70% of each day's reservations for a second release at 10 a.m. Eastern two days ahead. If you missed the 90-day release, that's the bigger one.

3. Check the minimum-stay rules

Several states relax minimums closer to the date: Vermont allows one-night stays within 7 days of arrival, and Maine allows one night, weekends included, for bookings made on or after July 1. A single night can be easier to find.

4. Stay nearby instead

Each campground page has a lodging map and, where we've checked them, private campgrounds nearby.

• Cadillac Summit Road (Acadia): Acadia National Park, Bar Harbor, ME
• Nickerson State Park: Brewster, MA (Cape Cod)
• Lafayette Place Campground: Franconia Notch State Park, NH
• Burton Island State Park: Lake Champlain, St. Albans, VT
• Sebago Lake State Park: Casco, ME
• Hammonasset Beach State Park: Madison, CT

What never works

Booking bots and resellers. State reservation systems ban automated booking, and a resold permit can be cancelled. This site never books for you and never checks booking sites automatically.