Visitors can descend to network of tunnels where slaves once worked to heat baths.

It is now possible to visit a previously sealed-off stretch of the labyrinthine network of tunnels under Rome's Baths of Caracalla thanks to a new itinerary which includes one of the surviving brick ovens.

The newly-opened underground space features a contemporary art installation, running until 29 September, created by artist Fabrizio Plessi and set to music by composer Michael Nyman.

Entitled Plessi at Caracalla: The Secret of Time, the display comprises 12 sculptural installations inspired by the baths and the brutal emperor Caracalla, using imagery of elements such as fire and water.

Plessi's installation highlights the “drama of a place where thousands of slaves … worked to maintain a perennial fire", Rome’s special superintendent Francesco Prosperetti told Agenzia Nazionale Stampa Associata in a recent interview.

The vast network of tunnels under the enormous complex housed 50 brick ovens which slaves fed with wood to heat the caldarium above.

The public baths were likely built between 212 and 216 AD, during the reigns of emperors Septimius Severus and Caracalla, and were in operation until the sixth century before falling into disuse and suffering major damage in the earthquake of 847.

For tickets and visiting details see Terme di Caracalla website.