There has been a fortified hill in Lieto (“Liedon Vanhalinna”) from the prehistoric age. According to excavations, the castle has been in use in the Late Bronze Age (1500-500 BC), in Middle Iron Age (500-700 AD, contested) and in the Middle Ages up to the end of the 14th century, when it was replaced by the "new castle" in Turku harbour.
During the first crusade (ca. 1155) to Finland Swedish army fought heavy battles against pagan Finnish people to conquer Lieto castle hill. After the victory Swedish fortified hill with stone and brick walls to defence the new city of Turku and christianity against Finnish and Novgorodians. There were several buildings, outer walls and a watch tower in the hill. When the Turku castle was completed Lieto castle lost the military value and was left to decay. The latest record of the existing castle date from the year 1438.
In the 1956 private landowners donated Lieto hill to the University of Turku, which has used hill for the archeological training. Nowadays there are some few ruins left of castle walls and buildings.
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.