Overtourism has long been a problem plaguing the cobblestone streets of Rome – with visions of the overcrowded Trevi Fountain and congested public transport striking fear into the hearts of locals each time peak season rolls around.

It has spurred local authorities to consider introducing visitor taxes on landmarks, among other measures – but tourists may be resisting its piazzas and historic monuments this year for a whole other reason.

For over 12 months, large swathes of the city have been shut off for construction work ahead of the 2025 Roman Catholic Holy Year, a celebration held every quarter of a century.

More than £1 billion from the state and £2.5 billion from the EU’s post-pandemic funds have gone towards overhauling tourist sites, parks and transport links – but the result, in the short-term at least, has been widespread discontent among locals and visitors alike.

Mayor Roberto Gualtieri has told Reuters that the upcoming Holy Year was “an unmissable opportunity to make structural changes … and transform Rome”, describing the finished renovation, which includes the creation of a new square by the Vatican as “a more sustainable, inclusive and innovative city”.

And the impressive total of 3,200 city-wide projects also includes the underground shifting of a major road junction and the sprucing up of the three Piazza Navona fountains and the Renaissance foundation outside the Parthenon.

But all that innovation – including a new Metro C station near the Colosseum, the city’s first automated metro line – is true to the old adage that Rome wasn’t built in a day, and some have been rudely surprised by the state of the city upon their arrival.

While the bulk of the work will be finished this year, the Metro C development won’t wrap up until 2034 – prompting travel blogger Gary Modica to urge travellers to “hit the pause button” for… the next decade.

“Construction trucks and pipes are everywhere,” Gary wrote after a visit in July. “Imagine this: You’ve saved up for your Roman adventure and there you are, ready to capture that iconic snap of the Colosseum.

“But wait, scaffolding blocks half the view, and a detour sends you on a wild goose chase through a maze of construction fencing. You say… ‘This wasn’t in the guidebook!’”

It was an experience echoed by The Telegraph’s senior travel writer Greg Dickinson during a recent trip – who was caught off guard by the well-meaning substitution of a blocked-off Trevi Fountain with “a little trough for tourists to fill with their pennies” in the meantime.

Dickinson also notes local concern over the timescale of the work – with one resident suggesting that “several projects won’t be finished until 2025”, putting the city in a precarious position to welcome the expected 35 million tourists celebrating the Holy Year.

There’s a chance some could be put off heading to Rome at all. Travellers on Reddit and TripAdvisor describe the “absolute mess” of a city as being “in its worst state possible” to other, would-be visitors – with more than one person handing low ratings to landmarks such as the Piazza Navona thanks to their “building site” appearance.

Others, though, may be happy to rearrange their holiday around the new-and-improved city’s gradual unveiling – even if, as Dickinson writes, the effect of a boarded-up Rome is akin to “eating a Michelin-starred meal while suffering from the flu”.