The islands are built among the reeds near the edge of the lake. The reeds are quite deceptive, the water here is about 100ft, 30m deep and the reeds float in the upper water column down to perhaps 10m, 30ft or more. So the reeds you see on the surface are just the upper tips of the plants. After rough weather some of the reeds are damaged and the root blocks float to the surface. These root rafts are about 20ft x 40ft, 6m x 12m in area. They are then cut apart and moved to a location to build a new island. The root blocks are then tied together to form the foundation of a new island and it can take anywhere from 18 to 36 or more root rafts to form a new island. These root rafts are then covered with cut reeds to form a dry platform that sits above the water. This platform is then anchored to the lake floor with a network of stones and ropes so it doesn't blow away to another part of the lake. Structures are then built on top of the island, including reed huts, kitchens, bathrooms, boat docks, viewing platforms, and so on. The reeds break down and decay over time, so every month another 2 tons of reeds need to be added to surface of the island. Typically several families live on each island and are often multi-generational, with grandparents, parents, and children living on each island. There are currently 137 islands and about 2000 people living on them. The advantage is that they don't pay property taxes, but they have no services and have to supply their own solar electricty and water tanks. Fresh water is obtained from clean areas of the reed marsh. Electricity is used mostly for lighting and charging cell phones so they have internet. Their food sources are mostly fish and birds. They have also created schools, churches, and medical clinics on the islands. The islanders regularly visit the nearby town of Puno for more serious medical needs and to trade fish and buy goods not available to them on the islands such as vegetables, grains, fruits, textiles, wood, metals, tools, and construction materials. Other important purchases include modern aluminum boats with outboard motors, and the gasoline to run them. Their main source of income is tourism, such as the sale of souvenirs and gifts, and stays at hostels, which are all very successful businesses. Each load of reeds added to the island causes it to sink a little. Eventually the foundation of the island is so weighed down with reeds that it touches the lake bed some 100 ft below. Once it touches the lake bed the reeds rot and break apart, and then the island sinks and is destroyed. This means the islands only last about 30 years. The islanders know this however and begin building a new island a few years in advance.