I voted 5-6 however, I am not really sure. I actually think it was more like 4-5. I know I had a tricycle before I was 3 as I had it before my sisters were born, as I turned 3 a couple of months before they were born. I had a bicycle with training wheels definitely by the time I was 4. But I cannot for anything remember when the training wheels were taken off. I can tell you where all my bikes as a child came from. Actually the same bike shop we just bought my mountain bike at. Who'd thought I'd buy a bike while visiting my parents in Ohio, while I live in NC. LOL The owner is the 3rd generation of the family to own and run that bike shop. I remember riding a lot as a child, actually through at least Jr High school age. I think it's around that time I started having a hard time finding bikes that would fit me properly, which has continued to this day.