The Ancient City of Iuliopolis is located 123 km northwest of Ankara, in the Gülşehri area of Çayırhan Town, Nallıhan District. The settlement, divided by the Aladağ Stream, was previously known as Sarılar Village. With the construction of the Sarıyar Dam in the 1950s, the city was submerged under the dam's waters. Under the scientific supervision of the Anatolian Civilizations Museum in Ankara, archaeological excavations were carried out in 1991, 2009, and subsequent years. In the southern part of the area, which served as a necropolis during the Hellenistic, Roman, and Byzantine periods, numerous findings from the Late Roman and Early Byzantine periods were identified during the 2023–2024 excavations. Remains of fortification walls, roads, and structures have been identified and documented. An Early Byzantine storage room was discovered during excavations in November 2024. No kitchen or storage room had been previously identified in the city. Five in situ terracotta pithoi were found side by side at the base of a wall. One of these pithoi is notable for having a Latin cross on its surface. Inside Pithoi No. 4, a bronze patera was discovered, while the soil fills within the storage room yielded various artifacts, including a terracotta loom weight, an iron axe, a glass unguentarium (tear bottle), a fragment of a marble column drum, a column base, an altar fragment, a sculpture fragment, two coins, ceramic sherds, as well as terracotta brick and roof tile fragments. Apart from the three-aisled church and burial structures dating to the Early Byzantine Period, the discovery of this storage room suggests the presence of a monastic complex in the area, where surplus production was stored. The five pithoi and other small finds identified during the study were analyzed through analogical comparison to date the storage facility. In light of the data obtained were provided into the architecture and socioeconomic structure of Iuliopolis, shedding light on the Late Roman and Early Byzantine Periods.