One of the original towers that guarded the fortress's main entrance has been found by archaeologists working at Neuenburg Castle in central Germany. They were taken aback by the tower's octagonal design, which was completed around the year 1100.

The Thuringian count Ludwig der Springer constructed Neuenburg Castle towards the end of the 11th century, and it was later enlarged during the 13th century. It is now one of Germany's biggest castles and is regarded as a cultural landmark of national importance.

Since 2022, the Neuenburg Castle, which stands above the town of Freyburg, has been the site of archaeological research by the State Office for Heritage Management and Archaeology Saxony-Anhalt. They concentrated their research on the 11,500 square meters of the outer bailey, one of Germany's largest outer baileys.

The researchers looked at a location where big stones had been found a few years earlier and compared it to the "Old Tower" location shown on three maps from the 19th and 20th centuries. Their excavation turned up the remnants of an octagonal structure with walls that were 1.7 meters thick and had a diameter of 10 meters. The tower was still standing, reaching a height of 2.2 meters, but it was once much taller. Even traces of a staircase and floors were discovered by the researchers.

A tower similar to this one was seen around 50 meters to the south. Both are a part of the castle's original fortification system, which included significant defensive features. At roughly the same period, a rampart composed of limestone gravel, an inner ring wall, and a second outer wall that ran parallel at a distance of about six to eight meters were all constructed. A roughly ten-meter-deep trench was built in front of this. The two octagonal towers in this section of the fortification must have made an impressive spectacle.

The tower's octagonal shape would have been extremely unusual for Germany in the eleventh century. It was seen as a breakthrough in castle construction, but it wasn't utilized frequently until the later 12th and 13th centuries, particularly under Holy Roman Emperor Frederick II (1220–1250). The experts hypothesize that the towers lining Constantinople's city walls may have served as a source of inspiration for the architects.

Prior to further improvements to the castle, which will include the construction of a new workshop and administrative building as well as a barrier-free entry to the outer castle, the government of Saxony-Anhalt is conducting archaeological research.