Archaeologists digging at Ancient Amphipolis in Central Macedonia, northern Greece, are poised to make an “exceptionally important find,” according to Prime Minister Antonis Samaras, who visited the site on Tuesday.

“It is certain that we are looking at an exceptionally important find,” he said after being guided around the Kasta Hill by archaeologist Katerina Peristeri.

“The land of Macedonia continues to move and surprise us, revealing from deep within its unique treasures, which combine to form the unique mosaic of Greek history of which all Greeks are very proud,” he added.

Archaeologists believe that the excavations are about to reveal an important tomb. According to Peristeri, who is the head of 28th Ephorate of Prehistoric and Classical Antiquities, excavations over the last two years at Kasta hill have revealed a unique grave circle which dates back to the last quarter of the 4th century BC.

“The main question the excavation will answer is regarding the identity of who has been buried here,” said Samaras.

Ancient Amphipolis was founded as an Athenian colony in 437 BC and conquered by Philip II of Macedon in 357 BC. The site is known for the Lion of Amphipolis, a 4-meter high monument.

There has been speculation that the tomb could contain the remains of Alexander the Great or his wife, Roxana, and their son, Alexander IV. Roxana and Alexander IV were murdered by Cassander.