The construction and development of Stonehenge is complicated to be fully known, the dates and details have been amongst other things have been decided by excavations, scientific dates and movement of the chalk.
It is estimated that Stonehenge was built about 3100BC and was built in three stages. The first stage was a large earthwork which had aubrey holes (round pits) which form a circle about 284 feet in diameter and a ditch.
The second stage about 2150 BC was 82 bluestones from the Preseli Mountains. They were placed to make a incomplete double circle. Also at this time The Avenue was built which aligns with the midsummer sunrise.
The third stage about 2000 BC was the Sarsen Stones, thought to be from the Marlborough Downs. These were placed in an a outer circle with a run of lintels, inside this circle five trilithons were put in a horse shoe shape, remains of these can still be seen.
A final stage about 1500 BC was done when the bluestones were moved to make a horseshoe and circle; this is what we see today.
The way the stones would of been transported would of been an amazing feat the journey from the Presili Mountains in South Wales would of been about 240 miles and the Marlborough Downs about a 25 mile journey, even though this would of still be a tough task the largest stone then was about 50 tonnes and it would of been impossible by water so had to be a complete journey by land. They would have been transported on land by sledges, rollers and ropes and would of been dragged and pulled and on water rafts would of been used.
Stonehenge is owned and managed by English Heritage and the surrounding land by The National Trust. Stonehenge was added to the list of World Heritage Sites in 1986 and is also a legally protected Scheduled Ancient Monument.
It is unsure why Stonehenge was built but there a many theories behind it including Merlin the Wizard had it built, it was a roman temple, the first academic effort was made by John Aubrey in 1640 who put it down to the Druids and in the late nineteenth century John Lubbock says it was done in the Bronze Age due to bronze items being found in the barrows. Most of these have been declared false because of the date of the stones.