The Cryptoporticus of Reims is is a very well preserved third century AD Roman passageway. At the time, Reims was a Gallo-Roman town known as Durocortorum.
Like other structures of this kind, the Cryptoporticus of Reims was a semi-subterranean arched passageway, the roof of which would have been a walkway. It would have been one of three such passageways surrounding the forum of Durocortorum.
The Cryptoporticus of Reims is an excellent example of this type of Roman architecture, particularly as it is so very well preserved.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.