Founded in 275 BC by Ptolemy II Philadelphus, Berenice was one of the most important harbours and trading posts on the Red Sea coast from about the 3rd to the 5th century AD. Remnants of the ancient town, including ruins of the Temple of Serapis, are located just south of the present-day village. Excavations are ongoing; between seasons, archaeologists cover the site to aid preservation, so there's not much to see outside the wonderfully clear water.
Berenice is located 150km south of Marsa Alam, which has the nearest airport. Buses (LE50, nine hours) departing from Hurghada, bound for Shalatein, stop in Berenice. You will need to arrange your own transport to get out to the ruins.
The nearest accommodation is just north of Berenice, along the coast around Hamata and Wadi Lahami Village. Outside of these coastal resorts there's little on offer in Berenice in terms of supplies. You can get basic dried food and tins in Berenice, and there may be a cafe open serving the usual coffee and a water pipe.
At the time of writing, security concerns made it difficult to travel south of Wadi Lahami Village.