Siwa has a long and ancient past: in late 2007, a human footprint was found that is thought to date back three million years, making it one of the oldest known human prints in the world. Flints discovered in the oasis show that it was inhabited in Palaeolithic and Neolithic times, but beyond that Siwa’s early history remains a mystery.

The oldest monuments in the oasis, including the Temple of the Oracle, date from the 26th dynasty, when Egypt was invaded by the Assyrians. Siwa’s Oracle of Amun was already famous then, and Egyptologists suspect it dates back to the earlier 21st dynasty, when the Amun priesthood became prominent throughout Egypt.

Such was the fame of Siwa’s oracle that its prophecies threatened the Persians, who invaded Egypt in 525 BC and ended the 26th dynasty. One of the Western Desert’s most persistent legends is of the lost army of Persian king Cambyses, which was sent to destroy the oracle but disappeared completely in the desert. This only helped increase the oracle’s prestige, reinforcing the political power of the Amun priesthood.

The oracle’s power – and with it, Siwa’s fame – grew throughout the ancient world. The young conqueror Alexander the Great led a small party on a perilous eight-day journey across the desert in 331 BC. It is believed that the priests of Amun, who was the supreme god of the Egyptian pantheon and later associated with the Greek god Zeus, declared him to be a son of the god.

The end of Roman rule, the collapse of the trade route and the gradual decline in the influence of oracles in general all contributed to Siwa’s gentle slide into obscurity. While Christianity spread through most of Egypt, there is no evidence that it ever reached Siwa, and priests continued to worship Amun here until the 6th century AD. The Muslim conquerors, who crossed the desert in AD 708, were defeated several times by the fierce Siwans. However, there was a cost to this isolation: it is said that by 1203 the population had declined to just 40 men, who moved from Aghurmi to found the new fortress-town of Shali. The oasis finally converted to Islam around the 12th century, and gradually built up wealth trading date and olive crops along the Nile Valley, and also with Libyan Fezzan and the Bedouins.

European travellers arrived at the end of the 18th century – WG Browne in 1792 and Frederick Hornemann in 1798 – but most were met with a hostile reception, and several narrowly escaped with their lives. Siwa was again visited in WWII, when the British and Italian/German forces chased each other in and out of Siwa and Jaghbub, 120km west in Libya. By then Siwa was politically incorporated into Egypt, but the oasis remained physically isolated until an asphalt road connected it to Marsa Matruh in the 1980s. As a result, Siwans still speak their own distinct Berber dialect and have a strong local culture, quite distinct from the rest of Egypt. The oasis is now home to some 21,000 Siwans and a few thousand Egyptians.