This is a large and splendid map by Reaper; to begin with, he decided not to put it on general release, but instead to distribute it to members of his clan (due to inflation, not Seven Man Clan any more, but Elite Forces - cool!) and to his online friends, with its recipients under strict instructions not to pass it on, but he later relented, and it can be downloaded from the usual sites.
As FeEdiKo pointed out to me, this is one of those cunning maps where, if you go to the bottom, you find you are at the top, which is fun. This place makes rather fuller use of the idea than
Fractal Remix did! The map is of an indoor Roman Arena, with plenty of room for crowds to watch from around the sawdust-strewn central killing ground. There are plenty of corridors off, and backstage areas, and a sniping gallery which you are unlikely ever to find the way into unless somebody shows you... the only drawback is that the central light above the arena flares something awful, so the sniping gallery is just about useless for actual sniping, and spectators would be well advised to wear sunglasses! This effect may also cause a very slight degree of lagginess, too.
But a large, stone-hewn, atmospheric and cunning arena, so if you get it, you certainly won't regret it.