How long did it take from the time you left Cairo until you came back?
The pyramids are right outside of Cairo... It's a very short ride depending on traffic to reach the desert (maybe a half hour).
Once you get to the desert, you can choose to either go in by Horse or Camel.
I would say that horse is probably the faster of the two options.
(Side note: there are tonz of peddlars that are gonna try to get you to hold onto there little souvineers and then after u have them, make u pay.)
I don't recall exactly how long the whole ordeal was exactly, but i would have to guess around 4 hours from the time we got there until we left, it can really vary depending on what you choose to do and how long you stop to take pictures etc.