We have visited most of the important temples around Ayutthaya Historical Park. Somehow we also managed to skip one or two. In any case, we advise that you need about two full days to cover most of the sites. This amount of time is the same whether you use a bike, a car, or a touring coach. Most visitors will only spend a few hours in the old capital, but this will not allow you to have a full overview of its culture and history.