Reservoir re-housed, historical artifacts moved or rare environments relocated. Examples include the temples of Abu Simbel (which were moved before the construction of the Aswan Dam to create Lake Nasser from the Nile in Egypt), the relocation of the village of Capel Celyn during the construction of Llyn Celyn, and the relocation of Borgo San Pietro of Petrella Salto during the construction of Lake Salto. Construction of a reservoir in a valley will usually need the river to be diverted during part of the build, often through a temporary tunnel or by-pass channel. In hilly regions, reservoirs are often constructed by
Structure relocation waters of Lake Nasser. In 1959, an international donation campaign began to save the monuments of Nubia: the southernmost relics of this ancient human civilisation. The salvage of the Abu Simbel temples began in 1964, and cost US $80 million. Between 1964 and 1968, the entire site was cut into large blocks, dismantled and reassembled in a new location – 65 m higher and 200 m back from the river, in what many consider one of the greatest feats of archaeological engineering. Today, thousands of tourists visit the temples daily. Guarded convoys of buses and cars depart twice a day