Dahab, Egypt. It is about one and a half hour drive from the larger city Sharm el-Sheik, which offers many of the same activities, but Dahab is much less touristy. It is my impression that the conditions for diving and surfing is much greater in Dahab, but the city is much smaller, and there is no beach and party culture. So dive/surfing connoisseurs take the extra drive to the more relaxed Dahab.
It's a small town on the southern Sinai peninsula, which mostly caters to divers and windsurfers (tourists and more permanent residents). It has only a few thousand residents, but over 50 dive shops. As a result, everybody in Dahab are connected to the dive community, and are very likely divers themselves. Due to the abundancy of dive shops and experts, many people (me included) take their first certification here. There are great dive spots for beginners accessible directly from the town centre.
It also has several great spots for advanced divers or tech divers, with plenty of deep underground caverns, the infamous Blue Hole, and wrecks like the famous SS Thistlegorm. Other world class diving spots are also accessible with a bit of travel by boat.
It is also reknowned for its windsurfing conditions. There's a big shallow sandbank, which offers strong, steady wind coupled with little waves. Outside the sansbank, I guess there are more waves, but we didn't see anyone out there. As opposed to windsurfing, I'm not sure the surfing is that great in Dahab, due to the smaller waves – but I am not sure.
It's a short 30min walk from the town, but I believe the windsurfers usually stay at hotels or resorts near the windsurfing facilities, and take a cheap taxi to the town for shopping or more restaurants.
Divers usually stay at hotels near the waterfront in the town centre itself, close to the dive shops, or even in the same building.
When we were there (2013) the place was almost devoid of tourists, due to the current situation in Egypt. I don't think that has changed now, a year later. That proved to be beneficial for us, since we got more attention from the dive masters, and all the dive spots were empty and undisturbed (I've heard tales of people who had to "queue up" in crowded dive spots).
As for the security threat, remember to check with the travel recommendations for your country. Currently (as it was then), they generally don't recommend travelling to Egypt with the exception of the common tourist destinations in Southern Sinai (Dahab and Sharm el-Sheikh included), but your mileage may vary.