The Roman city of Cemenelum was founded in the 1st century AD as a staging post for Roman troops in the Alpes Maritime region and it later became the regional capital. Favorably located, Cemenelum was chosen as the principal seat of the province of Alpes Maritimae by Augustus in 14 BC. Later, the Romans settled further inland, on the opposite side of the river Paillon. Remains of the town on the Hill of Cimiez date to the 3rd century AD.
The Amphitheater at the northern end of the site was originally built of wood and seated only 500-600. It was later rebuilt in stone during the Severan dynasty (AD 193-217) with its capacity expanded to 5000 persons. The vaulted remains at Nice may be compared to other small amphitheaters in garrison towns in the Roman Empire. Seating in the amphitheater reflected class distinctions between officers and enlisted men, with the structure at Nice-Cimiez divided into two sections reached by separate entrances.
The amphitheatre is not as big or as well-preserved as those found in Arles or Nimes, but along with the Roman baths and arena, visitors can gain a sense of wonder into Roman life by paying a visit to the archaeological museum (Musée Archéologique de Nice-Cimiez) on Avenue des Arènes.
The Roman baths complex is the largest known in Gaul.
First record of Kastelholma (or Kastelholm) castle is from the year 1388 in the contract of Queen Margaret I of Denmark, where a large portion of the inheritance of Bo Jonsson Grip was given to the queen. The heyday of the castle was in the 15th and 16th centuries when it was administrated by Danish and Swedish kings and stewards of the realms. Kastelhoma was expanded and enhanced several times.
In the end of 16th century castle was owned by the previous queen Catherine Jagellon (Stenbock), an enemy of the King of Sweden Eric XIV. King Eric conquered Kastelholma in 1599 and all defending officers were taken to Turku and executed. The castle was damaged under the siege and it took 30 years to renovate it.
In 1634 Åland was joined with the County of Åbo and Björneborg and Kastelholma lost its administrative status.