Shoal Cave

It is located north of Mossdeep City on Route 125, and is the only place in Pokémon Ruby, Sapphire, and Emerald where wild Spheal and Snorunt can be encountered. Shoal Cave uniquely features a high tide and low tide mechanic, where certain areas are only reachable during a specific time of day. The overall area accessible during high tide is smaller than during low tide. Due to the presence of an Ice Rock, Eevee can evolve into Glaceon on the lowest floor in Omega Ruby and Alpha Sapphire.