LEGO may have unknowingly taken some engineering inspiration from the ancient people of Britain. An image shared by English Heritage Stonehenge on Twitter offers “a rarely seen view of the top of one of the giant sarsen stones” in what looks “a bit like [an] early LEGO!”

Stonehenge is made of two types of stones, the smaller Pembroke Bluestones and the Wiltshire Sarsen sandstone, a type of sandstone that is found naturally across southern England, weighing on average about 25 tons with the largest, the Heel Stone, weighing 30 tons. The “LEGO” piece is made of sarsen, with its “protruding tenons” clearly visible.

LEGO even got in on the joke, responding that this is “where it all began.”

Mystery has shrouded the iconic site for centuries. Research suggests that the monument was built by an unknown group of ancient people over several stages sometime after 3000 BCE, but who, why, and how are questions that remain largely unanswered today.  

“The Stone Circle is a masterpiece of engineering, and building it would have taken huge effort from hundreds of well-organized people using only simple tools and technologies,” writes English Heritage, overseers of the ancient site in Wiltshire, southern England. It is widely agreed that the henge was continuously in use over two millennia for ceremonial purposes and mortuary practice during the Neolithic and Bronze age, between 3700 and 1600 BCE, though its exact purpose is largely unknown. A scale model of Stonehenge as it appeared 4,000 years ago shows that the henge had impressive acoustics (you can listen to what it might have sounded like here.) Pig bones found at the site revealed that thousands of people every year came to the site to feast and celebrate. Some contend that the large stones were placed on their hillside location as a way to celebrate the winter and summer solstices – though some have argued that may just be a coincidence.

Recent excavations have revealed a Neolithic “city” located just 2.5 kilometers (1 mile) away from the prehistoric monument and genetic analysis of ancient people living in Britain between 8500 BCE and 2500?BCE suggested that the nation’s earliest inhabitants may have originally been from the Mediterranean, and these newly adapted farmers may have been behind its impressive construction.

Stonehenge is made of more than 150 enormous stones transported from nearly 300 kilometers (180 miles) away. The giant “bluestones” weighing 2-3 tons were quarried in Wales in 3000 BCE, right around the same time as the first wave of Stonehenge’s construction, and may have been transported using a combination of ancient pullies, wedges, and sleds before constructors dragged them away.

UNESCO calls the World Heritage site the most “architecturally sophisticated prehistoric stone circle in the world” and contends that whatever its purpose, Stonehenge represents the “unique embodiment of our collective heritage."