After it was depicted in paintings by Charles Frederick de Brocktorff in the 1820s, the site was commonly referred to as the Brochtorff Circle, although it is not known who came up with this name.

According to the archaeologist David Trump, these names are misnomers because 'Stone Circles' in northern Europe and the British Isles refer to a different type of Neolithic structure.

[2] However, Ħal-Saflieni is a man-made carved structure, while the Xagħra Stone Circle consists of natural caves which were adapted into a cemetery.

There was limited activity from 3800 to 3000 BC, but pottery and dated bones demonstrate that burials were taking place in the caves and rock cut tomb, even though much of this material was probably reworked when the site was expanded and elaborated during the later Ggantija and Tarxien periods.

Thus most of the site activity dates from 3000 to 2400 BC, associated with the insertion of megalithic stones into the subterranean complex to form compartments for burial areas.

During the Bronze Age, the site was probably used for non-funerary domestic purposes, and remains from the Tarxien Cemetery and Borġ in-Nadur phases were uncovered in the area.

The fieldwork and post-excavation study was directed by David Trump, Caroline Malone and Simon Stoddart, assisted by Prof Anthony Bonanno.

[6][verification needed] These excavations revealed the remains of one of the largest funerary complexes in the Mediterranean, and led to a better understanding of the society who built Malta's megalithic temples.

It is the only stone-enclosed hypogeum in Europe, and the only prehistoric necropolis in Malta which was properly excavated – no records were kept when the human remains and artifacts at Ħal-Saflieni were cleared in the early 20th century.