The steep slope of the hill that rises from the Grand Temple to the Royal Citadel (tr. Büyükkale) was part of the Hattusa Old Town. This quarter of the city was protected by fortifications, at least from the 16th century BCE. There were many buildings erected on this slope, on the artificial terraces, localized among the rocks protruding from the ground.

The so-called Hillside House (tr. Yamaç Evi) is one of the largest of these houses, but also the best-preserved buildings of this type. In its heyday, it was a two-storey building, constructed on a rectangular plan with the sides 32 and 36 meters long. The archaeologists assume that it was not a residential house, but an administrative center. This theory is supported by the size of the main lobby (13 to 17 meters), situated on the reconstruction of the upper floor. The lower floor served as a warehouse and an archive where, during excavations in 1911 and from 1960 to 1963, substantial collections of clay tablets were found.

House on the Slope was destroyed by fire at the end of the 13 century BCE, and it was never rebuilt. Remnants of the burnt mudbrick walls in the back of the building have survived to the present. They are now protected by a modern wall.