Hmm...
I think it's called Ocean Side in the jap version and Seaside in SM All-Stars.
But on another note, if it really is called Seaside, ever wonder if that and Seaside Town, Sea, and Sunken Ship (from SMRPG) are the part of the same place (Seaside Kingdom, that is)?
Oh, I also forgot
Moleville and
Barrel Volcano (but it might be part of Nimbus Land)
The 1964th person