Where can I go to hunt for dragons? I've had most luck around Riften, but I've still only found 2 there. So can anyone tell me a place where dragons seem to show up a lot? Thanks!

I got six going from Rorikstead straight west to Markarth. Always seem to get a few on that trip.

Thanks! Every time I do this I encounter at least 2 dragons! Too bad they're blood dragons and kill me almost every time XD