At the time of Schliemann's excavations in 1876 six tholos tombs were known at Mycenae, the Treasury of Atreus, the Tomb of Clytemnestra, the Lion Tomb, the Epano Phournos, the Cyclopean Tomb and the Kato Phournos. Most of these had been seen by earlier travellers, such as Leake and Dodwell. Lord Sligo and Lord Elgin had conducted explorations in the Treasury of Atreus: Veli Pasha had attacked the Tomb of Clytemnestra, and apparently was responsible for the destruction of its dome. Steffen marks all these six on his excellent map of Mycenae and its environs. Schliemann in 1873 and 1876 was the first to begin the excavation of the tholos tombs. He made some tests in the Treasury of Atreus, and Mrs. Schliemann superintended the operations intended to clear the Tomb of Clytemnestra, but she was unable to complete them. By 1879 Stamatakes had cleared the dromos and chambers of the Treasury of Atreus, which, till then, as shewn clearly in the Elgin drawings preserved in the British Museum, were blocked with a large accumulation of earth. In 1886 Tsountas commenced his long and fruitful series of excavations, and among other important finds was rewarded by the discovery of three more tholos tombs.