The temple inside the “Golyama Kosmatka” Mound was built during the second half of the V century BC. The preserved colour ornaments on the wings of the marble gate of the chamber symbolise the main directions of the world and the cycle of time according to the Thracian beliefs. The magnificent golden wreath of the ruler, an exquisite wine goblet, knee-pieces and a helmet with plastic ornamentation, decorations of horse ammunition and other valuable artefacts have been found in the tomb. The remarkable bronze head of the statue of Seuthes III, ritually buried in front of the facade is an extraordinary expressive and detailed piece of art. It is an important evidence of the Orphic rituals not only on a national, but also on an international scale.

In 2004 in the “Golyama Kosmatka” Mound a monumental temple was discovered, with an entrance from the south, built during the second half of the V century BC.

The temple consists of a corridor, a passageway, a round chamber with high beehive roof, and a rectangular chamber, built as a sarcophagus from two monolithic stone blocks, each weighing over 60 tones. The three rooms are built of rectangular stone blocks and covered with stone plates. A two-winged marble gate closes the entrance of the round chamber. The upper parts of the wings have perfectly depicted images of God Dionysus. In the eastern section he is the personification of the Sun, and in the western section – of the Earth and the Night. The preserved colorful ornaments on the eastern section are in red, whereas those of the western section are in black color.

In the rectangular chamber there is a carved ritual bed and a ritual table. They had been covered with tissue made of golden thread, and after that, had been used to carry out a sumptuous burial of a ruler, honored as God. On the phial, the jug and the helmet, the name of Seuthes can be discerned, which proves that at the beginning of the III century BC Seuthes III – the famous Thracian ruler of the Odryssian Kingdom – was buried here. His capital Seutopolis is about 10 km to the southwest from the tomb, at the bottom of the present-day Koprinka Dam. The body had probably been cremated somewhere else because no remains have been found in the tomb. Instead, only the head of his statue, which had stood on a pedestal in the capital Seuthopolis, has been buried as the Orphic customs ordained. In the chamber were the personal belongings of the ruler, carefully arranged, as well as the gifts for his after-life – a golden wreath, two albastrons, golden wine goblet with decoration of floral ornaments, a silver gilded Mediterranean shell, a magnificent golden set for horse decoration, amphorae, a nearly complete set of armor – a helmet with silver male head ornamentation, a golden decoration of lion’s head in the middle of a leather breastplate, two bronze knee-pads decorated with the heads of goddesses, swords and sheaths decorated with golden ornaments, and a small knife with a golden hilt. After finishing the ritual, the few initiated ones who had taken part in it blocked up the entrance of the circular chamber and offered the horse of their ruler as a sacrifice, then blocked up the passageway too, ritually set fire on the corridor, and placed the bronze head of the ruler’s statue seven meters away from the facade of the temple.