Training spot.

I LOVED Blue Kentauruses. Awesome exp on 4x, no lie. I trained there from about 71-88, and I consistantly got about 5-6% per mob up until the 80's. The exp hardly slowed down, but if you're going to train there, be prepared to spend money. I don't know about anyone else, but I was burning about 1k pots (barbarians) per hour. It can add up. Best of luck to you sir.

Edit : Oh man, I forgot to mention. You might/probably will die the first couple times training there, but once you get the hang of it you'll do great.