Calais Lighthouse is a significant landmark as well as a navigational aid to ships and ferries using the Straits of Dover. There was a beacon at the summit of the watchtower from 1818. King Louis-Philippe in his plans to improve French ports decided the construction of a first-class lighthouse in Calais. This lighthouse started operating in 1848 and was electrified in 1883. After escaping the destruction of the Second World War it was automated in 1987.
The lighthouse is 53m high, its tower is octagonal outside and round inside with walls 1,90m at the base and 1,50m at the summit. The foundations descend 7,40m under the cellars. The staircase has 271 steps leading up to the lantern. The central light of the lighthouse is permanent and the lantern, whose panels shut off the light, turns around the light, giving 4 flashes of 2/10th of a second every 15 seconds.References:
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.