Careening a sailing vessel means to beach it at high tide in order, usually, to expose one side or another of the ship's hull for maintenance below the water line when the tide goes out. Small boats, as in the photo, need not always be laid over. The process could be assisted by securing a top halyard to a fixed object such as a tree or rock to pull the mast over as far as possible. Maintenance might include repairing damage caused by dry rot or cannon shot, tarring the exterior to reduce leaka… (More on Careening)