From Bulbapedia, the community-driven Pokémon encyclopedia.

Rind Island
タンカン島 Tankan Island
[[image:|250px]]
Info
Region	Orange Islands
Anime debut	The Wacky Watcher
Location of Rind Island in the Orange Islands.

Rind Island (Japanese: タンカン島 Tankan Island) is a tiny deserted island in the northern region of the Orange Archipelago.

Pokémon watchers come from around the world to see the pilgrimage and mass evolution of Magikarp here.

Its English name comes from the botanical term for the thick outer skin of a fruit, like a peel.

On the map from bundled DVD, it's misnamed Millsweet Island.