Oman has many spiritual sites, but the Sultan Qaboos Mosque always takes a very special place on the list. It was opened to the public in 2001 and lies proudly in Muscat, Oman's capital city. You'll love everything about its architectural design, and most importantly, the fact that it's not as crowded as most of the other religious attractions. Entrance to the mosque is free, but please note that you'll have to wear long-sleeved tops and long pants (or skirts) when you visit this place.