The Orthodox church of Hamina (The Church of Peter and Paul) was erected in 1832-37 on the place of burned Lutheran church. It was designed by Frenchman Louis Visconti whose most famous work is the tomb of Napoleon in Hôtel des Invalides.
The round-domed church was built in the Neoclassicism style with Byzantine features. There is a holy icon with St.Peter and Paul which was transferred to Hamina from Vyborg in 1742.
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.