How do I get out of cyrodiil sewers?

CombatPrayer

I have been looking for a way out and I keep getting back into combat zones. There is something that looks like a wayshrine but I cannot use it.

visionality

Just use the "Cyrodiil"-door in the sewers base. Brings you back to Cyrodiil and to the wayshrine at the spawning bases.

Nefas

You can also port to a friend or guildie from ONLY inside your alliamce's sewer base if you don't want to deal with Cyrodiil loading screen + another zone loading screen if you intend to leave Cyrodiil completely.