Windsor Castle is a residence of British monarchs (see map). The original castle was build in the 11th century. Through ages, it was rebuilt a couple of times.
The castle is widespread. To get to the inside of the main premises, you have to go alongside walls and smaller buildings. The greenery is well-taken care for. You can even take a look into the Queen’s garden (>>>). Unfortunately, you cannot take shots inside. It is also forbidden in the State Apartments, including the St. Georges Hall famous for the state banquets.
However, on the way back, at the Lower Ward, you can enjoy the Guard change ceremony. It is a real half an hour show (starts at 11.00). It is not merely a ‘guard change’. The guards are accompanied by a band. You can watch the full drill with loud shouts, listen to music, and see at the close the red and black guards’ clothing including bearskin (>>>). The ceremony is quite entertaining.