World’s largest Roman mosaic unveiled after 2,000 years — but some remains buried. ‘We are still digging.’

Rome wasn’t built in a day — and neither were its mosaics.

After 2,000 years, the public can finally get a look at “the Great Mosaic,” the largest Roman mosaic ever discovered.

“We are giving this unique wonder back to the city,” bragged Rome Mayor Roberto Gualtieri, who unveiled the restored masterpiece alongside another ancient fresco dubbed “The Painted City,” according to the Independent.

First spotted in the 1990s and fully dug up this year, the colossal 1st-century AD mosaic stands over 32 feet tall and stretches more than 52 feet across a wall under the Baths of Trajan, right near the Colosseum, The Times Of London reported.

“We think it’s the biggest wall mosaic ever found in the Roman world, and we are still digging to find where it stops,” teased archaeologist Francesco Pacetti.

Together with “The Painted City,” it forms the single largest mosaic complex on the planet.

Experts reckon the sprawling artwork once adorned a high-end private residence or even the infamous Domus Aurea — the lavish pleasure palace built by Emperor Nero.

It was buried in AD 109 when Emperor Trajan took over the plot to build his massive 15-acre public bathhouse.

Now, tourists can descend into the underground gallery to see the ancient marvels for themselves. Though chunks of it are missing, the artwork still packs a punch, showcasing life-size figures lounging around pillars alongside vivid blue and white tiles and gemstone remnants used to mimic shimmering sunlight.

The upper section shows theatrical scenes starring dynamic figures, while the lower level shows a stunning bird’s-eye view of a fortified port city — complete with a theater, temple, bustling public plazas, golden statues, and neighborhoods so detailed you can make out individual window frames.It was subsequently buried in AD109, whereupon Emperor Trajan designated the area for his 15-acre public baths — the world’s largest.

“It could be a real place or an idealized city, we are not sure,” Pacetti admitted.

If that coastal paradise actually existed, it was an “extremely important” hotspot, according to Rome’s cultural chief Claudio Parisi Presicce.

Even though digging continues, Mayor Gualtieri insisted “it was important not to wait any longer to open it to the public.”

For the trial run this fall, site officials are capping group sizes at 15 visitors to test how the fragile masterpiece handles crowd humidity before opening the floodgates to everyone.