Apostle Islands Sea Caves Crossing: the route, the season and the permits

Every leg out here is exposed Lake Superior open water, and the mainland sea caves are only safe in settled conditions. The points below are fixed geographic references, not an official route: the National Park Service does not publish a numbered water trail for the crossing. The park does publish exact GPS coordinates for every island campsite, which is the list to plan your nights from.

Trip-dependent; crossings between islands run several miles of open water each.

Parties launch at Meyers Beach and take out at Little Sand Bay; the route map lists every agency-sourced coordinate in between.

Open the Apostle Islands Sea Caves Crossing route map · compare it with the other nine trips

• Meyers Beach to Sand Island — the classic sea-caves crossing
• Little Sand Bay to Oak, Stockton and Rocky islands — the sheltered inner loop
• Outer island ring — multi-day, open-water crossings for experienced paddlers

Best window: Late June – early September.

A wilderness camping permit is required for every overnight stay in the national lakeshore, reserved in advance through Recreation.gov. Day paddling the mainland caves needs no permit, but every island night does.

Recreation.gov — Apostle Islands wilderness permits ↗

Full permit page for this trip

• Lake Superior cold water — hypothermia in minutes, even in July
• Squalls and steep, fast-building waves
• Falling rock and ice at the sea caves
• Black bears active on nearly every island
• Biting stable flies (unbothered by repellent)
• Long dead zones with no cell coverage behind the outer islands

Lake Superior water is clear but must be filtered or treated for Giardia and Cryptosporidium. Check the NOAA marine forecast for western Lake Superior before every crossing.

File a float plan with a shore contact, carry a VHF marine radio (Channel 16), and wear a whistle and signal mirror on your PFD. A dry suit or wetsuit is standard equipment here, not an upgrade.

• Sea caves weekend · 2 days — Meyers Beach to Sand Island and back — mainland sea caves, the Sand Island light and one reserved island campsite.
• Outer ring · 5 days — Little Sand Bay to Oak, Stockton and Rocky islands — longer crossings and real Lake Superior weather.
• Sand Island base camp · 3 days — Cross from Meyers Beach to Sand Island, camp two nights, and day-paddle the sea caves and lighthouse shore without moving camp or making long crossings.

Build your own dates in the Apostle Islands Sea Caves Crossing trip planner

One of the highest black-bear densities in the region — use the park's bear lockers or a canister. Bald eagles and migratory songbirds are everywhere; piping plover nesting beaches close seasonally.

Camp only at designated sites, store all food and scented items in the provided bear lockers or a bear canister, and leave glass containers at home.