A fragment of the world’s oldest and largest unsolved jigsaw puzzle, a 2,200-year-old map of Rome made of thousands of marble fragments, has been finally reunited to the other existing pieces, according to the Rome Cultural Heritage Superintendency.

Connecting to a large piece discovered in 1562, the new fragment bears an inscription that completes the word “Circus Flaminius.”

The map, known as Forma Urbis Romae, was carved into marble slabs between 203 and 211 A.D., during the rule of the emperor Septimius Severus.

Photos: Ancient Roman Mosaic Revealed

Only fragments remain today and most are held in the Capitoline museum. They cover just 10 percent the original map surface that once stood on a wall in the Templum Pacis (Temple of Peace).

The wall still survives today in a building near the 6th-century Church of Santi Cosma e Damiano. Rows of holes where the map was attached using bronze clamps can still be seen.

Pompeii Couple Reunited in Marble Inscription

Carved on 150 marble slabs, the 60-foot by 43-foot map detailed every building, street and staircase in Rome until it was partially ripped from the wall, probably to make lime for cement. What was left fell down and broke apart in hundreds of unrecognizable pieces.

Piecing the jigsaw puzzle together remains one of the great unsolved problems of archaeology. The first fragments were discovered in 1562. Since then, some 1200 pieces have been brought to light.

“Of these about 200 marble chips have been identified and ideally located on the modern topography,” the Superintendency said in a statement.

Pieces of Roman Sign Reunited After 2,000 Years

The new fragment was discovered in 2014 during work at the Palazzo Maffei Marescotti, a building owned by the Vatican.

The marble piece ended up there as it was likely recycled during the construction of the palace at the end of the 16th century.

The new fragment has allowed the researchers to piece together at least other three chunks of the huge puzzle, allowing a more comprehensive reading of an important area of ancient Rome.

Ancient Rome History Comes Alive With New App

“The fragment relates to plate 31 of the map, which is the present-day area of the Ghetto, one of the monumental areas of the ancient city, dominated by the Circus Flaminius, built in 220 BC to host the Plebeian games, and where a number of important public monuments stood,” the Superintendency said.

Pieced together with the other bits of plate 31, the new fragment will be on display at the Museum of Ara Pacis until March 17.