Just noticed bill's post.
I will counter your centuries with an even more difficult mileage..... 3 miles in 2 hrs!
Of course, I was riding behind my son. It is very difficult to ride a regular bike at 2 mph.
I think I should have walked. Still he can take off at a pretty good clip every so often.
3 miles is still pretty good for a kid who has been riding for a month.