The Tito Bustillo Cave is a prehistoric rock shelter located in the small town of Ribadesella. The cave was inhabited by humans (cro-magnon) before the year 10,000 BC. Due to the collapse of the rock, the original entrance to the cave was sealed thousands of years ago, which made it possible for preservation of objects, tools and wall paintings that were discovered in 1968. Based on those objects found in the cave, it is known that there was a significant human presence during the Magdalenian culture of the Upper Palaeolithic, but the cave was probably inhabited before that time.
The Tito Bustillo Cave has been designated a World Heritage Site, as part of the Cave of Altamira and Paleolithic Cave Art of Northern Spain, and it counts with 12 prehistorical paintings, making it one of the most complete examples of the prehistoric art in the north of Spain. The oldest of these paintings shows human figures and is around 33,000 years old, as determined by radiocarbon dating. Some scientists believe it could have been made by Neanderthals, though this theory hasn't been proven.
Some of the paintings represent animals: horses, deer, moose and even a marine animal (probably a whale) and they are believed to have had some kind of ritual purpose to improve their hunting. There is also a panel representing female genitalia and it is believed to have had the intention to invoke fertility. The oldest painting in the cave represents an anthropomorphic figure, part male, part female.
Apart from the paintings, some objects from the Magdalenian period were perfectly preserved. The most important ones are some harpoons made of bone and a carved staghorn of a goat head.
References: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.