In 1831 Mr. Franzen, the owner of the Salahmi Ironworks was given permission to establish a blast furnace and a bar-iron forge at Jyrkkäkoski. The early years were difficult, because Jyrkkäkoski was not at any close distance of main travel routes and sufficient labour was not available. In 1856, the ironworks was obtained by Paul Wahl & Co. as part of a larger consortium. A new Scottish-type blast furnace of English brick was erected at the site in 1874.
The ironworks produced pig and bar iron, as well as nails and cast products. In the early 1900s the Ironworks even had its own small steam boat. Many prominent cultural figures were seen at Jyrkkä, including the author Juhani Aho who courted the beautiful daughter of Brax, the manager of the works. The Jyrkkäkoski Works was in operation unti1 1919.
Finland’s National Board of Antiquities carried out conservation and reconstruction works at Jyrkkäkoski in 1996-98. The old ironworks has become an architectural attraction in North Savo. The blast furnaces now have impressive protective structures. In connection with the Scottish blast furnace is Ruukintupa, a cafeteria serving snacks. "Herrala", the manager’s residence dates from the 1830s and the log buildings in the yard area are even older.
Reference: Sonkajärvi Municipality
The Walls of Constantinople are a series of defensive stone walls that have surrounded and protected the city of Constantinople (today Istanbul) since its founding as the new capital of the Roman Empire by Constantine the Great. With numerous additions and modifications during their history, they were the last great fortification system of antiquity, and one of the most complex and elaborate systems ever built. They were also the largest and strongest fortification in both the ancient and medieval world.
Initially built by Constantine the Great, the walls surrounded the new city on all sides, protecting it against attack from both sea and land. As the city grew, the famous double line of the Theodosian Walls was built in the 5th century. Although the other sections of the walls were less elaborate, they were, when well-manned, almost impregnable for any medieval besieger.