St Sampson's Cathedral is one of the oldest churches in St. Petersburg. Rumor has it that it was in St. Sampson's Cathedral that Catherine II of Russia secretly married Grigory Potemkin in 1774.
The original wooden church was built in 1710 to honor Sampson the Hospitable. It was on the feast day of that saint that Peter the Great defeated Charles XII of Sweden in the Battle of Poltava. The existing church was built under Empress Anna to a design by Pietro Antonio Trezzini. It was consecrated in 1740. The tent-like belltower was built at a later date. The original church had only one dome; the four subsidiary domes were added in 1761.
The church was considerably renovated as part of the battle's bicentennial celebrations. A Rastrelliesque chapel was constructed on the grounds, and Peter I's address to his soldiers at Poltava was inscribed on the wall. It was at that time that the church was elevated to cathedral status. The parish was disbanded by the Soviets in the 1930s, and the building was converted into a warehouse. It was restored in the late 1970s and reopened in 2000 as a museum attached to St. Isaac's Cathedral.
The grave yard which surrounds the church has been filled for centuries. Some of the city's first foreign architects, including Jean-Baptiste Alexandre Le Blond and Domenico Trezzini, were buried there. The tomb of Artemy Volynsky and Pyotr Yeropkin (both executed exactly 31 years after the Poltava victory) is made by Alexander Opekushin (1885). The statue of Peter the Great in front of the cathedral was designed by Mark Antokolsky. It was removed by the Soviets and restored in 2003 as part of the city's tercentenary celebrations.
On 5th February 2017 the cathedral was transferred from the state to the Russian Orthodox Church at a ceremony in the cathedral.
The Arch of Constantine is situated between the Colosseum and the Palatine Hill. It was erected by the Roman Senate to commemorate Constantine I's victory over Maxentius at the Battle of Milvian Bridge in 312. Dedicated in 315, it is the largest Roman triumphal arch. The arch spans the Via triumphalis, the way taken by the emperors when they entered the city in triumph.
Though dedicated to Constantine, much of the decorative material incorporated earlier work from the time of the emperors Trajan (98-117), Hadrian (117-138) and Marcus Aurelius (161-180), and is thus a collage. The last of the existing triumphal arches in Rome, it is also the only one to make extensive use of spolia, reusing several major reliefs from 2nd century imperial monuments, which give a striking and famous stylistic contrast to the sculpture newly created for the arch.
The arch is 21 m high, 25.9 m wide and 7.4 m deep. Above the archways is placed the attic, composed of brickwork reveted (faced) with marble. A staircase within the arch is entered from a door at some height from the ground, on the west side, facing the Palatine Hill. The general design with a main part structured by detached columns and an attic with the main inscription above is modelled after the example of the Arch of Septimius Severus on the Roman Forum.