The archaeological site of Horreum Margi is located between the rivers Ravanica and Velika Morava, in the very center of Ćuprija.

Among the Roman sites in the Velika Morava valley mentioned in the ancient sources and modern literature, Horreum Margi - the Granary of Morava holds one of most prominent places. The fortress was situated on the Roman military road Via Militaris, as well as on the Velika Morava River, which served as an important communication route during the ancient period. The city’s strategic position enabled it to develop as a hub for grain collection and taxation, a craft and trade center, and in the 4th century, it become home to an imperial weapons manufacturing workshop.

The city was destroyed in the mid-5th century during the Hunnic invasion. In the early 11th century, the medieval settlement of Ravno emerged on the site of ancient Horreum, existing until the 13th century.

The first archaeological excavations of the fortress began between 1962 and 1964 and continued in 1978 and 1985–1990, led by the Military Museum in Belgrade and the Archaeological Institute in Belgrade. The most extensive work was carried out in the northeastern corner of the fortress, behind the modern museum building, where these excavations partially uncovered the remains of the northeastern tower.

The Cultural Heritage Preservation Institute Kragujevac conducted smaller-scale research in 2010 in front of the current museum building.

During 2018 and 2019, the Institute's expert team resumed excavations in the northeastern corner of the fortress, fully uncovering the northeastern tower, parts of the eastern and northern ramparts, as well as numerous archaeological materials from both the ancient and medieval periods.

After a pause in 2020, the Institute's team resumed excavations in 2021. During this phase, additional sections of the northern rampart and the area around the northeastern tower were uncovered. The excavations conducted in 2018, 2019, and 2021 were funded by the Ministry of Culture and Information of the Republic of Serbia and the Municipality of Ćuprija. In addition to the Institute’s staff, the expert team included archaeologists from Ćuprija, Jagodina, Paraćin, and Belgrade.

The completed works have provided a better understanding of this part of the fortress and the architectural characteristics of this highly significant ancient fortification. This progress has paved the way for further conservation and presentation efforts for this section of the ancient city.