History of Finland between 150000 BC - 4001 BC
If confirmed, the oldest archeological site in Finland would be the Wolf Cave in Kristinestad, in Ostrobothnia. Excavations are currently underway, and if the so far presented estimates hold true, the site would be the only pre-glacial (Neanderthal) site so far discovered in the Nordic Countries, and it is approximately 125,000 years old.
The last ice age in the area of the modern-day Finland ended c. 9000 BCE. Starting about that time, people migrated to the area of Finland from the Kunda and - possibly - Swiderian cultures, and they are believed to be ancestors of today's Finnish and Sami people in Finland. The oldest confirmed evidence of the post-glacial human settlements in Finland are from the area of Ristola in Lahti and from Orimattila, from c. 8900 BCE. Finland has been continuously inhabited at least since the end of the last ice age, up to date.
The earliest post-glacial inhabitants of the present-day area of Finland were probably mainly seasonal hunter-gatherers. Their artifacts discovered are known to represent the Suomusjärvi and the Kunda cultures. Among finds is the net of Antrea, the oldest fishing net known ever to have been excavated (calibrated carbon dating: c. 8300 BCE).
Reference: Wikipedia
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.