Ride

Player's Handbook v.3.5 (PH)3.5

Key Ability: DEX
Trained Only: false
Armor Check Penalty: false

You can ride a mount, be it a horse, riding dog, griffon, dragon, or some other kind of creature suited for riding. If you attempt to ride a creature that is ill suited as a mount (such as most bipedal creatures), you take a -5 penalty on your Ride checks.