A dolmen (/ˈdɒlmɛn/) is a type of single-chamber megalithic tomb, usually consisting of two or more vertical megaliths supporting a large flat horizontal capstone ("table"), although there are also more complex variants. Most date from the early Neolithic (4000–3000 BC). Dolmens were typically covered with earth or smaller stones to form a tumulus. In many instances, that covering has weathered away, leaving only the stone "skeleton" of the burial mound intact.