Once, a long time ago when I was working on a civil engineering project in the Middle East, I happened to take a couple of days off for sightseeing with some colleagues. Among the places we went to was Gebel Musa (جبل موسى, "Moses Mountain" in Arabic), the mountain commonly associated with biblical Mt Sinai. The mountain, and the tiny Orthodox monastery of St Katherine at its feet, were a pretty spooky place.
To get there you gradually left civilization behind and wended your way into this tangled, remote wilderness -- sort of a knot of barren, steep, rocky mountains all huddled together (I think it's a ring dike, for the geologically inclined). The land felt bizarrely empty, and must have been even more so in Moses's day, before the monastery was built.
The mountaintops there were bright, airy, very dry, and very silent places. If you were hungry and/or thirsty enough, you probably wouldn't need any hallucinogens to start having visions.
There's some uncertainty about whether Gebel Musa is the "real" mountain referred to in the OT ( הר סיני, Har Sinai in Hebrew). It was originally believed to be a different mountain nearby (Gebel Serbal). It's also supposed to be the highest mountain, which would be Gebel Katherîna, also in the same cluster of peaks. But the local Bedouin claimed that Gebel Musa was the real thing, and that's where the Orthodox monks decided to build their monastery, so nowadays Gebel Musa gets marketed as being the "true" Mt Sinai.
Over the past 20 years, a "city" of ~5000 people has apparently been constructed around the monastery, complete with paved highways, tourist village, a bank, places to buy stuff, etc., all fed by water piped across the desert from the Nile.
The area still has strange effects on people. Anwar Sadat was fond of the region, and had a vacation home there. After the peace agreement with Israel, Sadat personally granted permission for the Belgian artist Jean Verame to construct some "landscape art" in a wadi (dry valley) west of the mountain, as a way to commemorate the peace accord. Verame basically painted a bunch of huge boulders with blue paint, claiming that the color blue was symbolic of peace, or something like that. (Wikipedia reports that he received a grant of ten tons of blue paint).
As I said, even for those not religiously inclined nor under the influence of chemical hallucinogens, it's a strange kind of place .....