[NEED HELP] Quake maps in Xonotic

Is it possible to convert Q1 and Q2 maps to Nexuiz/Xonotic ones? If yes, how?
I would like to play them in Xonotic.
PS. What is Quake III: King?

For what it's worth, we have servers running the Quake 1 campaigns, they can be found in the in-game server list as named:
Quake 1 Nostalgia Trip! (SMB)
Quake: Scourge of Armagon, Nostalgic Edition! (SMB)
Quake: Dissolution of Eternity, Nostalgic Edition! (SMB)


Xonotic runs on the DarkPlaces engine, so the Quake maps are pretty much directly compatible (although, support for Quake 2 maps is relatively new).

Thanks Mario, do you know what is Quake III: King?