User blog comment:Emily Windsnap/How old are the Merlin characters?/@comment-24492510-20151206105732

Basing on all the proofs I found out on the Internet, I think that in the first episode the ages are these:

Merlin: 17

Arthur: 20

Morgana: 22

Guinevere: 21

The other characters... Uther: late 40's/early 50's, Gaius: early 70's. Morgause (when she first appeared) was probably in her early 30's. Nimuah... very old!