Thracian Domed Tomb "Kuhata Mogila" (the Hollow Mound)

The Thracian Domed Tomb "Kuhata Mogila" (the Hollow Mound) — officially known as the Ancient Domed Tomb of Pomorie — is the largest Thracian tomb ever discovered in Bulgaria and the only monument of its kind on the entire Balkan Peninsula, located approximately 1 km northwest of the town of Pomorie, 300 metres from the Pomorie–Burgas road, near the Pomorie Experimental Station for Viticulture and Pomiculture, in Pomorie Municipality, Burgas Region. It is a national monument of culture, a branch of the Pomorie Historical Museum, and is currently being prepared for nomination as a UNESCO World Heritage Site — which, if approved, would be the first Bulgarian addition to the UNESCO list in over 40 years. In 1975, 200 metres northwest of the tomb, a separate burial mound was discovered containing the rich burial of the Thracian priestess and healer Leseskepra, who lived at the end of the 1st century AD.The tomb dates from the 2nd–4th centuries AD — a period of Roman dominance — and is an original and architecturally unique combination of a typical Thracian domed burial monument and a Roman mausoleum (heroon). The burial mound under which it is built is 8 metres high and has a diameter of approximately 60 metres, with an elliptical base and a slightly oval apex. The structure itself consists of a long entrance corridor (dromos) of 22 metres and a large circular chamber with a diameter of 11.60 metres and a height of 5.50 metres. At the centre of the chamber rises a hollow column 3.30 metres in diameter, which widens towards the top and merges with the outer wall — giving the structure its popular name, "the Hollow Mound." From the interior wall of this hollow column there was originally a spiral stone staircase leading to the surface of the mound. Along the circumferential wall of the chamber are five niches, in which the urns of the deceased were presumably placed. The construction technique combines limestone masonry and Roman brick in a sophisticated alternating-course system, with the vaults executed entirely in brick — an advanced technology for the period. Architects and engineers from around the world continue to study the monument today, as the precise method by which its uniquely shaped dome was constructed in the 2nd–4th centuries has not been definitively established. The structure was closed with bolts from the inside, suggesting multiple use over time.The scientific hypothesis accepted by most scholars is that the complex served as a heroon — a mausoleum and ritual sanctuary — of a wealthy Thracian family of Anchialos, in which religious rites connected with the cult of the sun were performed. According to this interpretation, advanced by the eminent Thracologist Alexander Fol, the priests divined the will of the god Sabazios (known by day as Apollo) through the force of sunbeams penetrating the hollow column when the sun reached its zenith; when the sun descended to the "lower hemisphere," fire was lit on an altar-hearth and the god (now called Dionysus) was invoked through the flames reflected against the night sky. An alternative scholarly view holds that the structure is exclusively a Roman mausoleum that was subsequently covered in Thracian fashion with an earthen mound. A minority opinion proposes it functioned as an astronomical observatory. No burial chamber was found in the structure; it was looted in antiquity, and almost no artefacts were recovered — only faint traces of dark green paint on the mortar plaster suggest the interior was once decorated with frescoes.The name "Kuhata Mogila" originates from the discovery of the tomb by two shepherds who, while grazing their flocks, broke through the top of the mound and entered inside. Systematic scholarly research began when the Škorpil brothers — Czech-Bulgarian archaeologists Karel and Herman Škorpil — visited Anchialos in the late 19th century and made the first drawings and sketches. The tomb was restored in 1958–1959 and declared an architectural monument in 1965. It is open to visitors from April to October (Tuesday to Sunday, 10:00–18:00 in summer; 10:00–17:00 in shoulder season; closed Mondays); outside the active season it is accessible by prior arrangement with the Pomorie Historical Museum on 0596/22008. Access is via a 300-metre asphalted side road turning left from the Burgas–Pomorie direction opposite the fish market, with a small car park at the entrance.