Kaaba
You may have seen a rectangular Black Stone on TV wherein heaps of Muslims go around and serenade. This Black Stone is known as the Kaaba. It is the most sacrosanct place in the Islam religion and Muslims feel super honored just to be in a similar zone with the Kaaba.
Sadly, not every person finds the opportunity to see the Kaaba face to face as it is situated in Makkah (Mecca). However, it is the most gone by point of interest in all of Saudi Arabia.