Israeli engineering firm Rolzur and Jerusalem’s largest burial society, Kehillat Yerushalayim, have devised a plan to radically change how Jerusalemites dispose of their dead by building a modern system of burial caves, a throwback to a practice discontinued some two millennia ago,

as shown in footage from Wednesday. Planners of Jerusalem’s newest necropolis, a massive underground complex, say it will eventually hold more than 20,000 bodies.

“We had a big problem of places to be buried in Jerusalem,” said Kehillat Yerushalayim Funeral Director Uri Miller. “You can imagine that if we have around 2000 burials a year and each grave takes around 70 centimeters (27 inches) multiplied by 2 meters (6.6 feet), then after [a] few years there is no place in Jerusalem to be buried.”

“It’s an environmental solution and it also saves a lot of place, you know, instead of having new cemeteries it’s a good solution,” said Rolzur CEO Ari Glazer. “And we hope also [that] it will be around the world because it suits many cities around the world.”