Road bicycles make handy means to get around in certain areas, but keeping spare 700C wheels around makes them even more useful. These thin, compact wheels are most commonly paired with conventional road bikes, but there are other options.
Due to their design, attempting to use 700C wheels with other kinds of frame isn't advised. Their lower overall weight makes them a boon to a road cyclist in the wind or on a hill though. Keeping a few extras keeps your bike in good shape.