All along the banks of Lake Titicaca grows a special type of reed called the Totora. The Totora is unique becuase of its hollow root system, these special roots allow chunks of soil to be cut off from the land and hauled out into the lake. Once brought into the water, these cubes of soil will actually float. This allowed the Uros to build huts and other structures on top of the floating blocks out of those very same reeds. So when they were attacked, the Uros were able to flee to their floating homes which had already been constructed in the lake, and simply push them farther from shore.
But the Totora reeds came with even more benefits, the white inner parts of the reed were edible, and even useful in making medicine. This meant that when combined with fish, the Uros people could provide themselves with both the food and water they needed to survive. Soon the Uros tribe decided to live on the water full time, and do away with their former land based lifestyle. They soon had domesticated cormorants which they tied to their rafts and used to catch fish for themselves. And later even began farming Ibis like chicken, raising them for both their meat and eggs. Life in the floating villages had become easy and peaceful, and unless an opposing tribe was willing to build a fleet to come after them they would likely never come under attack. But unfortunately, with the rise of the Incan Empire, that is exactly what happened.
The Inca soon arrived and conquered all of the tribes on the shores of the lake, finally being surrounded, and with Incan fleets being built on the shore, the Uros had no choice but to surrender. Over the next century they slowly began to lose their language as they engaged in trade with the larger Aymara tribe. The Incan Empire was later conquered by the Spanish Empire but this brought little changes for the Uros, who were able to isolate themselves from the political dealings outside their lake.
Slowly they began to regain independence, and reduce foreign influence on their communities, moving them to the middle of the lake to be as far away from the shore as possible. This isolation continued until 1986 when a huge storm came through Lake Titicaca that did enormous damage to their village. Finally deciding it was time to reconnect with the world, the Uros tribe moved back towards the shore near the city of Puno, and ended their period of political isolation. Today of the 5,500 Uros remaining, most of them live on the shore, but many still live in Lake Titicaca on their floating houses, and have begun to embrace modern living. Those who have jobs often work in tourism, selling trinkets to people who come to their floating village. Most boats now have gas engines, many homes have solar panels, and their is even a floating radio station playing traditional Uros music. But all of this can still be seen besides the traditional Uros watchtower, floating over the lake with ever vigilant guards. Today the watchtowers are their to protect against thieves instead of raiders, but traditional construction of such pieces is valued highly, since very few people know the Uros written language, knowledge of how to build many of their floating structures has to be passed down directly from father to son. A reminder perhaps, of why they came to the lake all those centuries ago.
Here we can see an Uros man explaining how the floating village is built. The large blocks of soil below the house are buoyant, keeping it lifted above the water, for added height and buoyancy several layers of reeds are added to the soil block, on top of which is placed the reed house. The lower layers of reeds will rot, meaning they have to be continually renewed by fresh cut reeds every few weeks. It is a process that requires continuous work and maintenance.