The Temple of Hercules Victor is a monopteros, a round temple of Greek 'peripteral' design completely encircled by a colonnade. Dating from the later 2nd century BC, and perhaps erected by L. Mummius Achaicus, conqueror of the Achaeans and destroyer of Corinth, the temple is 14.8 m in diameter and consists of a circular cella within a concentric ring of twenty Corinthian columns. These elements supported an architrave and roof, which have disappeared. The original wall of the cella, built of travertine and marble blocks, and nineteen of the originally twenty columns remain but the current tile roof was added later. Palladio's published reconstruction suggested a dome, though this was apparently erroneous. The temple is the earliest surviving marble building in Rome.
By 1132 the temple had been converted to a church, known as Santo Stefano alle Carozze. Additional restorations (and a fresco over the altar) were made in 1475. A plaque in the floor was dedicated by Sixtus IV. In the 17th century the church was rededicated to Santa Maria del Sole.
References:The Broch of Clickimin is a large and well preserved, though somewhat restored broch near Lerwick. Originally built on an island in Clickimin Loch (now increased in size by silting and drainage), it was approached by a stone causeway. The water-level in the loch was reduced in 1874, leaving the broch high and dry. The broch is situated within a walled enclosure and, unusually for brochs, features a large 'blockhouse' between the opening in the enclosure and the broch itself. Another unusual feature is a stone slab featuring sculptured footprints, located in the causeway which approached the site. Situated across the loch is the Clickimin Leisure Centre.