Short answers, pulled from the story.
Capri is located in the Tyrrhenian Sea off the tip of the Sorrento Peninsula, on the south side of the Gulf of Naples in the Campania region of Italy. The island lies approximately 5 km from the mainland and has an area of 10.4 square kilometres.
Tiberius moved permanently to Capri in AD 27 and governed the Roman Empire from the island until his death in AD 37. According to the historian Tacitus, he built twelve villas there; the most famous, Villa Jovis, is one of the best-preserved Roman villas in Italy.
The Blue Grotto is a sea cave on the northwest coast of Capri, illuminated by light entering through a submerged opening. The German August Kopisch published an account of his 1826 rediscovery of the cave, significantly boosting the island's fame across Europe.
Capri attracted Somerset Maugham, Norman Douglas, Compton Mackenzie, Maxim Gorky, Axel Munthe, Romaine Brooks, and Oscar Wilde, among many others. Lenin visited in 1908 as a guest of Gorky, and painters John Singer Sargent and Charles Caryl Coleman also worked there.
Monte Solaro is the highest point on Capri, rising to 589 metres (1,932 ft). It is situated in the western part of the island, in the area known as Anacapri.
Capri is accessible by ferry and hydrofoil from Naples (Molo Beverello and Calata di Massa), Sorrento, Positano, and Amalfi. The island has no airport; the nearest airports are Naples International (NAP) and Salerno Costa d'Amalfi (QSR). Vehicles are restricted from April through November.