Lake Tess is a large lake located in Winters, Foggyland in EarthBound. It is home to the legendary lake monster known has Tessie, along with a club of campers dedicated to watching for it. The lake can only be crossed from north to south through a combination of the Bubble Monkey and Tessie. The only major location in Winters north of Lake Tess is Snow Wood Boarding School; Dungeon Man's first dungeon, Rainy Circle, Stonehenge, and Dr. Andonuts's lab can all be found south of the lake.
In the Mother 1+2 Art Book, early concept art of Lake Tess showed that there was originally no land strip; it appears that Tessie was intended tolift Jeff up in a boat or let him ride on of its humps. The Bubble Monkey can only be seen in one of the drawings.