In 2005, together with archaeologist Zachi Zweig, Barkay established the Temple Mount Sifting Project, a project funded by the Ir David Foundation and dedicated to recovering archaeological artifacts from 400 truckloads of earth removed from the Temple Mount by the Waqf and Israeli Islamic movement during 1996-2001. The construction included the establishment of the underground so-called El-Marwani Mosque at an ancient structure known since medieval times as Solomon's Stables, excavating a huge pit as an entrance to the structure, and reducing the platform level at the area north to the entrance.