The monuments of the old Talmis, which was the name of the original site of Kalabsha now disappeared under the waters of Nasser Lake, were moved to its present location at New Kalabsha (Challal) in 1970. Amenhotep II of the 18th dynasty founded the original temple, but the actual one was built by the Roman Emperor Octavius Augustus (30 BC to 14 AD) who dedicated it to the Nubian god Mandulis, identified with Ra and Min. There are also remains of an earlier temple from the Ptolemaic era.

The design of the temple is the same as that of the Ptolemaic era, with two pylons, courtyard, Hypostyle hall and three sanctuary rooms. Unlike other Ptolemaic temples, the building does not follow a straight axis so, the first pylon creates a trapezoid with the first courtyard. The first courtyard once had columns on three sides with very few reliefs and some Meroitic inscriptions of King Kharamadoye and King, Silko who conquered the Nubian Blemmyes. After the vestibule, there are three chambers including The Pronaos (a chamber preceding the sanctuary) and The Naos, or the sanctuary where statues of gods were located. There are also scenes representing the king worshiping Mandulis, Horus, Min and other Deities.