The research of the area began in 1972 – 74 with the excavations of the Inner Defensive Wall. Inside the wall there was a monumental building discovered, above which, another building with mosaic floor was built. At the end of the 4^th or the beginning of the 5^th century, both of the buildings were cut with the foundations of the fortification wall. In 1981, new excavations on a smaller scale were also undertaken. In these campaigns the monumental building was called Building with Arches.

The systematic excavations began in 2003 and they continuously last up to 2009. During these campaigns, the excavated area has the working name of Roman Forum.

The building is located at the eastern terrace of the town, close to the Inner Defensive Wall.

There are a few phases of construction and renovation. It is a very positive circumstance that the building was abandoned after the destruction and it wasn’t treated as a source of building material.  The entire wall decoration and other architectural elements are found in situ.

The Building with Arches was erected at the end of the 1^st or the beginning of the 2^nd century AD. It has a rectangular plan with two apsidal halls on the western side. The walls are made of tiles and stone with massive pilasters connected by arches. The walls of the upper floor were designed in the same manner. Short after the construction, reliefs of green and pink marble were applied to lower zones of the walls while the upper parts were fresco and stucco decorated. The floors of the apsidal halls were designed in the opus sectile, with pink and green marble slabs. Gilded sculptures stood in the fresco decorated niches. The entrance of the building is located between the two halls.

At the beginning of the 4^th century the building was out of use and inside the big rectangular room a cistern was located. A drainage channel connected the cistern with the Small Bath to the west. The passage to the apsidal halls was closed and a building with massive steps was constructed on top of the entrance. It is poorly preserved and is supposed to be a small pagan temple. Towards the end of the 4^th century the buildings went out of use and the area was used as a cemetery. Somewhere in the first half of the 6^th century the walls from the upper floor of the original building collapsed over the graves. Traces of flood were very obvious in the soil that covered the destruction.  

The Building with Arches is still not completely excavated, but it is clear that this was a magnificent public building which was probably located close to the town’s forum.