They are one of the most famous sights in Venice, Italy.
The gondola has been a mode of transport through the narrow canals since the 11th Century, but now it is facing one of its toughest challenges – overweight tourists.
A new capacity limit has been placed on the famed rowing boats because the increased girth of visitors is causing some to sink.
The gondola "da nolo", used for more traditional tours through the canals, will now be limited to five people, down from six, while the larger gondola "da parada", which traverse the Grand Canal, will now hold 12 people instead of 14.
Andrea Balbi, president of Venice's gondoliers' association, told the Guardian that tourists "weigh a bit more".
"Unlike in a lift, where there's a message that says 'only six people or a maximum weight', we don't have scales to weigh people, and so we reduced the number of passengers," said Balbi.
Raoul Roveratto, who is president of the association of substitute gondoliers, was a bit blunter.
"Tourists are now overweight. From some countries, bombs load (on to the boats). And when [the boat] is fully loaded, the hull sinks and water enters," he told Italian publication La Repubblica.
"Advancing with over half a tonne of meat on board is dangerous."
A gondola costs around €30,000 ($A48,600) and there are 433 gondoliers and 180 substitute gondoliers.
In recent years Venice had been suffering from the effects of overtourism, however, it is now welcoming visitors once again after being closed for lockdown. Italy was one of the worst-hit countries in the initial wave of Covid-19.
See also: How to explore Venice without the crowds