From Cairo, Bahareya is the most accessible of the real desert oases. The main town of Bawiti (which is what most people mean when they talk about Bahareya) is an excellent base for trips into the White and Black deserts or to a range of sites around the oasis itself. However, the town isn't much of a destination in and of itself. This will hit home especially hard if you arrive by bus. The middle of town is a low, ugly sprawl of concrete buildings and ad hoc kiosks, and SUVs fresh from the desert, their roof-racks piled high with spare tires and boxes of water, churn up clouds of dust. If this place could talk, it'd say, "Let the adventure begin."
It wasn't always like this. During the Ptolemaic and subsequent Roman periods (around 2,000 years ago), the oasis was a rich and fertile agricultural center and may have had a population of up to half a million people. It was also the site of a massive necropolis, which was recently rediscovered by archaeologists in 1993 after a donkey fell in a hole. It has already yielded more than 100 mummies and is thought to contain as many as 10,000 more. The site of the necropolis hasn't yet been developed as a tourist site, but a few of the mummies are on display in Bawiti.
Note: There is no ATM in Bahareya, and no one at the time of writing was accepting credit cards, so you must carry cash. There is a place to change currency (and hotels should be happy to accept U.S. dollars and euros at the going rate), but that's it. Fortunately, Bahareya is also a low- to no-crime zone.