|Grasslands in Ohio|
wilderness (212 references),
and the Earth itself (342).
There are also references to the sea (81),
the seashore (24, almost always in connection with borders),
and the deep (8, referring to the ocean).
Other than the accounts in 1 Nephi and Ether of crossing the ocean, and a few references to Moses and the Red Sea, there are no accounts of the Nephites and Lamanites interacting with the sea, apart from Hagoth in Alma 63. The sea is always referred to as a border; i.e., a place beyond which no one went. Presumably the story of Hagoth made the cut (Mormon's editing process) because launching a boat into the sea was so unusual.
In Helaman 3, Mormon twice mentions "shipping" but doesn't indicate if this was by river or by sea.