Corruption of Azim
Every year at the summer solstice the Orcish clans from the southern plains gather together to celebrate at this location. This yearly ritual gathering is largely what keeps the orcs from devolving into further chaos. As it stands, however, the various clans do not really interact much aside from the festival.
The site is the location of the final battle between the Orcs and the Drow in a war that occurred many centuries ago. There are individual monuments to the Orc chieftains that united, temporarily, to drive off the Dark Elves. The Orc tribes take great pride in being a direct descendant of one of these chieftains, and only direct descendants are allowed to compete for the positions of champion, a year long station of guarding the site and the shrines. These days, however, most Orcs are descendants, so really any of them can compete in the trials and games to see who will be champions each year.