Another postcard from South America, this time from Peru, thanks to dear Jane.
These are the Uros islands, on Lake Titicaca, located between Peru and Bolivia. The islands were built by the Uros people, hence the name, and are inhabited by them to date. They are constructed of reeds, which the Uros people also use to build their homes and boats.
The islands float, and can be moved if necessary (they were originally build like this in case they came under attack).