CAIRO (AP) — A boat belonging to an Egyptian pharaoh is being assembled in full view at the Grand Egyptian Museum’s exhibition hall.

Staff began piecing together the cedarwood boat, one of two that were found that belong to King Khufu, Tuesday morning as dozens of visitors watched.

The assembly of the 42-meter (137-foot) -long vessel, which sits next to its already-assembled twin that has been on display, is expected to take around four years, according to Issa Zeidan, head of restoration at the Grand Egyptian Museum. It contains 1,650 wooden pieces.

King Khufu ruled ancient Egypt more than 4,500 years ago and built the Great Pyramid of Giza.

“You’re witnessing today one of the most important restoration projects in the 21st century,” said Tourism and Antiquities Minister Sherif Fathy, who attended the event.

The $1 billion museum, also known as GEM, was touted as the world’s largest when it was lavishly inaugurated last month. It's home to nearly 50,000 artifacts, including the collection of treasures from the tomb of the famed King Tutankhamun, which was discovered in 1922. The museum, located near the pyramids at the edge of Cairo, is expected to boost Egypt’s tourism revenues and help bolster its ailing economy.

The boat was one of two discovered in 1954, opposite the southern side of the Great Pyramid. The excavation of its wooden parts began in 2014, according to the museum’s website.

The exact purpose of the boats remains unclear, but experts believe they were either used to transport King Khufu’s body during his funeral or were meant to be used for his afterlife journey with the sun god Ra, according to the museum.