The excavations of Spyridon Marinatos and Georgios Korres at the site of Gouvalari, about 1 km northeast of the modern village of Koukounara, revealed a cemetery of Mycenaean tholos tombs. Small tholos tombs up to about 3 m in diameter had been built into earthen mounds and contained burials mainly from the early Mycenaean period. A short distance to the west of these earthen mounds and along the Arapis stream, two even larger tholos tombs were excavated, which, although looted, yielded remarkable finds that are exhibited in the Archaeological Museum of Pylos.

The southernmost of the two tholos tombs has a diameter of 6.25 m and was particularly rich in grave goods. It yielded pieces of painted ceramic vases with various decorative moitifs, numerous small and thin sheets of gold foil, beads of semi-precious stones, stone arrowheads, a gold bead with spiral and granulated decoration, seal stones with animal representations and a scene of a duel between two warriors, as well as dozens of boar tusks from helmets. The period of use of the tomb extends from the 16th to the 13th century BC. Extensive remains of funeral pyre and animal sacrifices accompanied by ceramic pots have also been found and are associated with intensive ancestor worship rituals during historical times.