Off the top of my head i cannot recall the dimensions for a 60gallon tank. I think they might be tall and narrow though, unless you get a 60Gallon breeder.
When you plan for an adult beardie, remember that you want a tank that is long but also wide so a full grown beardie (up to 22inches) can turn around. I would say the best aquariums for bearded dragons are either a 75gallon, (4ftLx2ftWx2ftH roughly...) or a 90gallon which has the same dimensions as a 75 but is taller. I have my adult female beardie (20inches) in a 90gallon right now and she seems to have plenty of room.
The other way to go are the "breeder" tanks, which come in 40, 50, and 60. These tanks are roughly 3ftLx2ftW and their lengths vary. All three sizes have the same length and width, but get a couple inches taller each time.
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0.1 Bearded dragon
0.1 mexican kingsnake
1.0.2 Leopard Gecko's
0.0.1 Rose Hair Tarantula
1.0 BTS
0.0.1 Reverse Okeetee Corn
0.1 Bullmastiff
4.1 Cats