Egypt has inaugurated its long-delayed Grand Egyptian Museum on Saturday, a megaproject aiming to give the country’s millennia-old heritage a rich, modern display.

Two decades in the making, the museum located near the Giza Pyramids and Sphinx is the centerpiece of the government’s bid to boost Egypt’s tourism industry and bring cash into the troubled economy.

Hundreds of drones created a light show in the sky, depicting well-known Egyptian gods like Isis and Osiris and the pyramids.

At the elaborate grand opening ceremony, attended by a number of European and Arab royals and other presidents and prime ministers, Egyptian President Abdel-Fattah el-Sissi appealed to the nation, and international community.

He called on attendees to “make this museum a platform for dialogue, a destination for knowledge, a forum for humanity, and a beacon for all who love life and believe in the value of humankind.”

El-Sissi also posed with delegates from more than 70 countries, including members of the royal families from Belgium, Spain, Denmark, Jordan, Gulf nations and Japan, and a number of European and regional presidents and prime ministers.

The museum, known as GEM, is one of several megaprojects championed by el-Sissi since he took office in 2014.

He embarked on massive investments in infrastructure with the aim of reviving an economy weakened by decades of stagnation and battered by the unrest that followed the 2011 Arab Spring uprising.

Construction on the $1 billion project began in 2005 under then-President Hosni Mubarak.

But work was interrupted by turmoil surrounding the 2011 uprising that brought down Mubarak.

Further delays ensued, and a planned grand opening over the summer had to be put off after the 12-day-long war between Israel and Iran erupted in June.