Mount Kalaga National Park
Forest, canyons and off-road trails along the northern border.
Overview
Mount Kalaga occupies Lummox County along Leonida's northern edge, and it is the one part of the map with no coastline at all — forests, canyons, rivers and trails instead, closer in feel to Providence Canyon than to Miami. Hunting, fishing and off-road trails are the draw, and the people who live out here are as far from Vice City as the terrain is.
Sources
Rockstar Newswire — Official character bios, region descriptions and screenshot releases.