ARCHAEOLOGICAL EXPLORATIONS IN ST. SOPHIA BASILICA (Yunian Meshekov – meshekov@abv.bg) The first archaeological explorations in the area under the floor of St. Sophia Basilica were carried out by Bogdan Filov in 1910. In 2010, grave No. 1 was explored, oriented east – west, 1.85 m in length, 85 cm in width and 62 cm in depth, situated across the western wall of the western extension of the nave of Church 1 built in the beginning of the 4th century AD. The grave was built of fragmentary and intact square bricks, 35 – 37 cm long, bonded with mortar. It was covered with a stone slab. The western wall of the grave was partly destroyed during the construction of the wall of Church 1. The skeletons were disturbed and belonged to three deceased, male and female, 20 – 30 years old. Iron nails and carbonized wood were found, indicating the existence of wooden coffin (coffins). The grave dated to the late 3rd – beginning of the 4th century AD.