Marine archaeologists utilizing advanced multi-beam sonar and underwater ROVs have identified a 400-meter-long alignment of monolithic stones on the seabed off the coast of the Isles of Scilly. The discovery, nicknamed the 'Avenue of the Deep,' consists of over 60 upright granite pillars, some reaching three meters in height, arranged in a precise double row that appears to align with the midwinter sunset of the Neolithic era.
Researchers believe the site was a major ritual center that was inundated approximately 4,000 years ago as sea levels rose following the last glacial period. Divers have recovered flint tools and fragments of grooved ware pottery from the silt surrounding the base of the stones, suggesting the site was a focal point for communal gatherings and celestial observations for coastal inhabitants long before the islands were separated from the mainland.