The Silver Cloud, which docked at the city's port at the weekend, can accommodate up to 400 people in its 196 cabins, some of which have already been allotted to the US men's and women's Olympic basketball teams, the general directorate of the Maua port terminal said.
The US delegation reserved all the cabins for the Olympics, and the ship, with all its amenities and attractions, will become practically a floating US embassy during the Games.
Rio's revitalized port is considered to be one of the main Olympic legacies and will attract thousands of tourists because of the gigantic screens that have been installed there for people to watch Olympic events and also other entertainment associated with the Games.
However, people who visit the port will have difficulty approaching the Silver Cloud due to the heavy security detachment deployed around the vessel.
A fence made of bulletproof material will keep the public away from the US athletes, who will be guarded by some 250 Federal Police officers.
"The Federal Police will also have two boats ... that they will use to prevent navigation near the vessel," said Maua port terminal operations director Alexandre Gomes.
The US ship is anchored at a site far from the docking spaces reserved for the many cruise ships that will visit Rio during the Games.