The Grotto of Tiberius is the most spectacular part of the Roman villa of Sperlonga. The enormous natural ravine is preceded by a large rectangular fish pond of sea water that housed an artificial island in the center that served as a summer caenatio, or the place where Tiberius and his court ate in the summer.
The grotto was decorated with marble statues of enormous artistic value dedicated to the saga of Ulysses and sculpted by Greek artists from Rhodes. It is thought that these famous craftsmen stayed in the villa to finish the statues previously sketched in the workshop. The bottom of the grotto was decorated with frescoes and masonry works that divided the room into rooms and alcoves. Near the alcove, the remains of frescoes and decorations created with local shells and the spaces where the beds were probably placed are still visible.
Above the external opening of the grotto there was the statue of a beautiful Ganymede kidnapped by the eagle Zeus. The fish pond communicates with the circular pool in the center of the cave where the sculptural group of the attack on the monster of Scylla, the most majestic of the four, stood out in a scenic position. Then there was the group of the blinding of Polyphemus, that of the abduction of the Palladium and that of Ulysses dragging the body of Achilles.