Los Santos Forum
The Los Santos Forum is the main stadium servicing Los Santos, and is located at the southeast end of the city, in the border of East Beach and Playa del Seville. It resembles a miniature version of the Great Western Forum (a.k.a. the Los Angeles Forum) in the city of Inglewood, the city which Idlewood was based on.
This is the location for a stadium race called 8-Track, since the track inside the stadium is shaped like the number 8. A Monster and a Hotring Racer will spawn near the entrance when that race is passed. The stadium is unique for having a jumbo TV showing camera fly-bys around the stadium.
Also, around the forum, there is one Gang Tag which is needed to be sprayed by the player using a Spray Can. Collecting all 100 of these rewards you with four weapons and a few ticks closer to 100%.