The picture was published by a user in the Facebook group 'Anima Vesuviana' last Thursday and shows an ugly plastic and steel tap stuffed into the mouth of the Fountain of Abundance in Pompeii.
The ancient fountain provides drinking water for the thousands of guests who visit the Unesco World Heritage site each year.
Over previous years, the fountain was tapped by a more elegant brass faucet, but this was recently changed during maintenance at the site and was clearly not to everybody's taste.
After being uploaded the picture was shared more than 5,500 times.
“It's Ok to replace a tap, but there are better ways of working on a 2,000 year-old sculpture,” wrote Laura Noviello, who manages the Facebook group 'Anima Vesuviana'.
After the online protests, the architectural superintendent of Pompeii reverted back to the previous brass taps, much to the delight of Noviello.
"The credit is not mine, but to see such a strong reaction moves the soul," she wrote.
But not everyone was satisfied. Many people believe the tap should be removed altogether and that the water should flow continuously from the mouth of the fountain.
“It's still ugly!” wrote one Facebook user.