The Crypta Neapolitana is an ancient Roman tunnel near Naples. It was built in 37 BC, and is over 700 metres long.
The tunnel passes beneath the Posillipo hill and connects Naples with the so-called Phlegrean Fields and the town of Pozzuoli along the road known as the via Domiziana.
The eastern Piedigrotta entrance is now enclosed within an archaeological park, and the site of the villa of Vedius Pollio, and later imperial villa. The site is also noteworthy for the presence of the so-called Virgil's tomb, as well as the tomb of the Italian poet Giacomo Leopardi. Three secondary tunnels end in openings overhanging the bay, providing light and ventilation.
The name Grotta Seiano (Sejanus's cave) comes from the infamous Lucius Aelius Sejanus, prefect of Tiberius, who according to tradition, commissioned its enlargement in the first century AD. The first tunnel was built by the architect Lucius Cocceius Auctus for Agrippa during the civil war between Octavian and Sextus Pompeius in c.37 BC to connect the villa of Vedius Pollio and other patrician villas of Pausilypon (ancient Posillipo) to the ports of Puteoli and Cumae. The tunnel is one of a number of such works in the Naples area built by Cocceius.
The tunnel was still in use as a roadway until superseded by two modern tunnels in the early 20th century, and shows extensive restoration done by the architects of the Bourbon dynasty of Naples. During the Second World War it was used as a bomb shelter for the inhabitants of Bagnoli; the war and some landslides during the fifties put it back into a state of neglect. Today it has been restored as an archaeological site.References:
The Château du Haut-Koenigsbourg is situated in a strategic area on a rocky spur overlooking the Upper Rhine Plain, it was used by successive powers from the Middle Ages until the Thirty Years' War when it was abandoned. From 1900 to 1908 it was rebuilt at the behest of the German kaiser Wilhelm II. Today it is a major tourist site, attracting more than 500,000 visitors a year.
The first records of a castle built by the Hohenstaufens date back to 1147. The fortress changed its name to Koenigsburg (royal castle) around 1157. The castle was handed over to the Tiersteins by the Habsburgs following its destruction in 1462. They rebuilt and enlarged it, installing a defensive system designed to withstand artillery fire.
The fortification work accomplished over the 15th century did not suffice to keep the Swedish artillery at bay during the Thirty Years War, and the defences were overrun.