To get to Pryce's gym is, get/battle Red Gyarados. Then you'll see Lance at the sign. Talk to him and he'll teleport all the way back to Mahogany Town. Go to the shop and you'll see him. After you beat Team Rocket, then there. You can go now.
In the mahogany gym
Mahogany town
Take a dump on the gameboy
You have to beat the gym leader, Pryce, in Mahogany City.
you beat it
The Mahogany City gym leader is not in Cianwood. He is in the gym in Mahogany, not anywhere else.
brain.com plc
Go up to Lake Rage and catch the shiny Garydos. Then go through the Rockets Hideout.
fail...
mahogany town
the next gym is @ Mahogany Town
After the mahogany gym you must go to the radio tower in goldenrod and defeat team rocket.