The legendary Ear of Dionysius is the most famous cave in Syracuse. It’s called this way for its ear shape and above all for its remarkable acoustic properties which amplify the sounds inside it. Its name was given by the painter Michelangelo da Caravaggio. According to the legend, the tyrant Dionysus used it as a jail and he used to eavesdrop on the prisoners’ conversations.
This cave was dug in Greek/Roman times as a water storage for Syracuse. A narrow tunnel was dug first. This tunnel was widened by digging down and sideways afterwards, giving the cave its unusual shape. The small narrow tunnel is still visible on the top of this artificial cave. An earthquake struck this area causing damage, and the cave became unusable for water storage afterwards.References:
Kristiansten Fortress was built to protect the city against attack from the east. Construction was finished in 1685. General Johan Caspar von Cicignon, who was chief inspector of kuks fortifications, was responsible for the new town plan of Trondheim after the great fire of 18 April 1681. He also made the plans for the construction of Kristiansten Fortress.
The fortress was built during the period from 1682 to 1684 and strengthened to a complete defence fortification in 1691 by building an advanced post Kristiandsands bastion in the east and in 1695 with the now vanished Møllenberg skanse by the river Nidelven. These fortifications were encircled by a continuous palisade and thereby connected to the fortified city. In 1750 the fortress was modernized with new bastions and casemates to protect against mortar artillery.