Minecraft wiki entry for Minecart, associated text: When a boat is placed in a minecart‌[Java Edition only], the minecart travels faster on rails, approximately as fast as on powered rails. The movement in the boat minecart is glitchy and moving forward with the W key moves the cart backward relative to the player, and vice versa for moving backward with the S key. The minecart also moves on the rail-less ground at a crawling speed, but it does not float in the water despite being in a boat.