In modern times, the Sinai territory has been held for a time by Israel after wars with Egypt in 1956 and 1967, but in accordance with peace treaties is today again part of Egypt.
The Sinai is hot, dry and rugged, a wilderness that the Israelites after the Exodus became well familiar with. It was the place of their Wilderness Journey in the years before entering the promised land. The north part of the Sinai is mostly desert, while the southern area has numerous steep, craggy mountains - one of which we know as Mount Sinai, where Moses received The Ten Commandments from God.
The peninsula gets its outline, and its mountains, from the earth's dynamic "plate tectonics" - the surface sections of the planet's crust are very slowly separating in some places, colliding in others. See Earthquake!
Fact Finder: How many years did the Israelites spend in Sinai after the
(a) 7 (b) 20 (c) 40 (d) 70