At Lake Windermere, Derwent Water, and Ullswater you can rent rowboats (most are big enough for a family of four).
There are some rowboats at Ullswater that only fit one person.
mnli hypothesis: There are some rowboats at Ullswater that only fit one person. premise: At Lake Windermere, Derwent Water, and Ullswater you can rent rowboats (most are big enough for a family of four).