Well for me about 1-3 miles would be a distance I would be fine biking as a commute or to go to the store for a few items. In a compact major city this could cover everything you could need, grocery stores, doctors, liquor store, post office, yoy name it. In some suburbs you might have to drive 5-10 miles to get to some of these things and a bike become more time consuming and more of a physical activity.