Where is Bagon? There is no Dragon Training Grounds, and I can't find..

Have you tried looking in the metoer falls place. I don't know if it is the same as Pokemon R & S. But there is a place where you use waterfall and surf and there is a place in the cave where water is. Ill make a diagram for that looks like this.L=Land W=Water _ or I = border or seprate from water from land. Enter =E
_______
I LLLLLLL I
I_________I
>>>>I WWWW I
^ I WWWW I
use surf >>>>> I WWWW I
I WWWW I
I WWWW I
I WWWW I
IIIIIIIEIIIIIIIIIIII

You can find Bagon at meteor falls after you get the HM Waterfall.

You can find Bagon in Meteor Falls.But in order to get it, you must have Surf and Waterfall.Here's what you do. Enter Meteor Falls from Fallorbar's side and keep going left until you see the first surfing spot. Surf there. Go up until you see a waterfall. Use water fall then go up the stairs. You should be in a whole different part of Meteor Falls.

Manuever your way through until you see a surfing spot.(Not the one with rocks!) Make your way up until you see a hole. Go inside. Surf across. You should find TM2 Dragon Claw.

Also you will find wild Pokemon including Bagon.(Bagon is very rare.) Keep walking around until you find a Bagon. When you've caught a Bagon exit the whole and backtrack to get out of Meteor Falls. Or simply use an escape rope. You've caught Bagon!

P.S. Pokemon in the second area will be levels 20-40.