Inspired by the threads about climbing in South FL...

I'm a South FL native. As such, I always thought that anything over... let's say 300 ft. was a mountain. This apparently is not the case. So, what is it that makes a mountain a mountain and not a hill?



These are two of the popular climbs here - Mt. Katsuragi (left) and Mt. Kongo (right). IIRC, Katsuragi goes from 0 to ~1800 ft. in ~7 km. Kongo is about the same, but over 11 or 13 km. Are these hills or mountains?