A recent experiment suggests that the Stonehenge, one of the most renowned heritage sites in the world located in the United Kingdom, was actually easy to build contrary to past research that says otherwise.

Barney Harris, a researcher for University College London, wanted to determine how many people are needed to move one of the stones, which stands up to 30 feet tall and weighs about 25 tonnes on the average, to create the Neolithic ring of stone slabs located in Wiltshire, England.

To do this, Harris and his co-workers gathered volunteers to move a 1-tonne stone, which is about half the size of Stonehenge’s smallest stone, according to Science Alert.

Harris initially expected that it would take up to 15 people to move the stone and up to 50 people to lift it. To his surprise, it took only 10 people to move the stone about 10 feet every five seconds, which equals one mile per hour.

Harris concluded based on the experiment that a team composing of 20 people can move even the smallest portion of Stonehenge with ease. However, they didn’t determine as to how many people would be needed to lift the stones into the air.

To move the stone, the 10 people  in the experiment did not actually move it with their own power. Rather, they used a sledge system that positioned the logs on the ground and then pulled the stones over them.

The logs were tied to the bottom of the stone so that it would have less friction, according to The Marshall Town.

The Stonehenge, which is older than the oldest tree in Great Britain, was created 5,000 years ago. Builders took about 1,500 years to finish it. It is one of the UK’s most popular tourist attractions and was added in UNESCO’s list of World Heritage Sites in 1986.