Raft

Rafts are usually kept afloat by using any combination of buoyant materials such as wood, sealed barrels, or inflated air chambers (such as pontoons), and are typically not propelled by an engine.

Large rafts made of balsa logs and using sails for navigation were important in maritime trade on the Pacific Ocean coast of South America from pre-Columbian times until the 19th century.

Such rafts consist of matted clumps of vegetation that has been swept off the dry land by a storm, tsunami, tide, earthquake or similar event; in modern times[when?]

They stay afloat by its natural buoyancy and can travel for hundreds, even thousands of miles and are ultimately destroyed by wave action and decomposition, or make landfall.

For amphibians, reptiles, and small mammals, in particular, but for many invertebrates as well, such rafts of vegetation were often the only means by which they could reach and – if they were lucky – colonize oceanic islands before human-built vehicles provided another mode of transport.