Superman: Crashes 'Supergirl' Set ... Nice Shinguards, Bro (Pics)

Here it is ... the first time Superman has touched down on the set of "Supergirl" ... and it's bad news for anyone planning to kick the guy below the knees.

Check out Tyler Hoechlin in his full Kal-El getup on the set of the CW show in Vancouver -- the dude looks pretty good ... he's even got the front hair curl in full effect.

By the way, Supes even took a few selfies with some of the people on the set ... 'cause that's how a super hero gotta do these days.