In the Late Bronze Age, warrior chieftains (and family) were buried in decorated Tholos tombs, round stone subterranean tombs with vaulted roofs. The room so created is called a thalamos. They were usually built on slopes or into hills. Burials could be put in pits, cists, or into shaft graves cut through the floor of the thalamos.
The largest tholos tomb found at Mycenae is called "the Treasury of Atreus," following Pausanias (2nd century A.D.). It has a side room probably for the burials proper. The walls may have been decorated in relief sculptures. The main room probably held parallel rows of bronze rosettes.
Source: Lesson 19 - Dartmouth -The Prehistoric Archaeology of the Aegean
Also Known As: Beehive tombs