The forecastle is the upper deck of a sailing ship forward of the foremast, or, historically, the forward part of a ship with the sailors' living quarters. Related to its latter meaning is the phrase
Replica of the Victoria, the only one of Ferdinand Magellan's five ships to return to Spain in 1522, showing its forecastle (left/foremost), quarterdeck (middle right), and poop deck (far right/aftmost).