🇬🇧 United Kingdom · Earthwork
Silbury Hill
Late Neolithic 2400–2300 BCE · Late Neolithic Britons (Grooved Ware)
Europe's tallest prehistoric mound – 39-m artificial hill with unknown purpose.
🇬🇧 United Kingdom · Megalith
Adam's Grave
Early Neolithic · Cotswold-Severn / Wessex
Chambered long barrow on Walkers Hill above Alton Barnes, 70 m, c.3650 BCE.