About 3000 BC new people apparently arrived in the Aegean, perhaps from Asia Minor. They used bronze for their weapons and tools, thus introducing the Bronze Age to the area. On the mainland their villages appear to have been small independent units, often protected by thick walls; over time, the buildings on Crete and in the Cyclades became more complex. Burials were communal throughout the Aegean, but burial practices varied. On the mainland, pit graves and some of more elaborate construction were common; in the Cyclades, stone-lined burial chambers (cists); and on Crete, circular stone tombs, rectangular ossuaries (bone depositories), and caves. All had places for cult offerings, and the dead were often buried with beautiful objects.