Excavations at Avebury have revealed one megalithic stone which could be among Britain's largest, weighing around 100 tons and rivalling Stonehenge.
The Avebury stone circle is 3,500 years old
Archaeologists made the surprise find during preparations to straighten the stones, which have been leaning for at least 300 years.
The project was undertaken at the 3,500-year-old stone circle in Wiltshire, because engineers feared the megaliths might collapse.
The team from the universities of Wales, Leicester and Southampton
found the stone, which is about 14 ft (4.4m) high above ground, goes down at least seven ft (2.2m) below the ground surface and may go down to
10 ft (3m).
Amanda Chadburn, of English Heritage, said: "We were amazed when we discovered that the
stone went so much deeper than we expected.
"Ground penetrating radar and probing had suggested it existed to only about one-and-a-half to three feet below the surface.
"It is absolutely enormous and could weigh as much as the trilithon at