The "Tomb of Atreus" is located less than a mile from the entrance to Mycenae.
It is one of many "tholos" or "beehive" tombs in the area, and dates from around 1250 BC.
It's a marvel of engineering and uses the same type of "corbelling' that was seen in the well at Mycenae.
The corbelling in the tomb is much more refined though.

It is unknown exactly who was buried here, but Schliemann decided it was most likely the tomb of Atreus himself,
because of its monumental size. It is obviously the tomb of some very important person.
The engineering and design of these "beehive" tombs is remarkable as some of the stones weigh over 100 tons.