Mine is 3.1 and has been walking since 10 months of age.
He is unstoppable. He will walk for miles with an occasional ride on shoulders. I know of others who still go in pushchair for a five minute walk (disclaimer: not knocking pushchair use at all)
Today we went out at 1pm to walk to the swings about 3/4 mile away, then we walked a long way back (about 1.5 - 2 miles) as an example.
He doesn't sleep though (bed 8.30, up at 6 kind of guy, and wakes in night)
Are you getting grief from someone? I think children vary so much in all ways.