Team Fortress 2/arena watchtower

Watchtower is an official community-created map. Unlike other Arena maps, it has much higher emphasis on vertical movement.

Sniper
Watchtower is a great Sniper map, featuring long sightlines as well as vantage points with good view of almost the entire map, making a good Sniper a deadly threat. You're also pretty exposed, so it's not recommended that you stay in scope too long and always be prepared for close confrontations. Enemies walking on the pipes are extremely predictable and thus should be easy to headshot. You can snipe on top of the wooden fence, the "islands" that serves as the base of the higher pipes or from inside the Watchtower.