Elmer van Buuren has spent 20 years waiting for night trains to come back into fashion.

A former guard on the Dutch railway, van Buuren recently noticed that a growing number of passengers wanted to swap high-speed rail or low-cost flying for the slower pace of the sleeper carriage. So he turned from enthusiast to entrepreneur and along with a business partner crowdfunded the launch of their own train company, European Sleeper.

“Until a couple of years ago, everyone thought sleeper trains were a thing of the past and something for hopeless romantics with their heads in the 19th century. That is just not the case,” van Buuren said.

Europe’s big rail operators have also launched new routes but the renaissance of the sleeper, long a byword for a lost age of travel, is being held back by a more modern problem: a shortage of suitable carriages.

Sleepers are particularly popular with business travellers, who can swap a late-night flight and hotel stay for a train trip that arrives in a city centre in time for a morning meeting. For leisure travellers the appeal lies more in the unique rhythms of the journey, such as a nightcap in Munich before waking to views of the Adriatic as the train pulls into Venice.

Passengers can typically choose between several classes of travel, from private rooms to the traditional “couchettes”, where several people share a berth.

Rail operators have complained of a rush for rolling stock as demand booms, with van Buuren saying it had been “extremely difficult” to find suitable carriages for the European Sleeper, which plans to launch this year a train linking Brussels, Amsterdam and Berlin on three nights a week.

He believes there is enough demand to have a nightly service instead and to launch new routes to southern Europe and Scandinavia — if only he could find more trains.

“It is definitely holding us back,” van Buuren said.

Many old carriages were sold off or mothballed as night trains fell into decline decades ago because of competition from high-speed rail and airlines.

The remaining carriages, some up to 60 years old, are increasingly unsuitable for more discerning modern travellers, who are less inclined to spend the night sharing a small compartment with strangers and expect modern facilities such as an en-suite toilet.

Only an average of six new carriages per year were ordered between 2001 and 2017, meaning it would take 250 years to replace the continent’s nearly 1,500 dedicated night train carriages with more suitable modern equipment, according to a 2021 European Commission report.

But things have since picked up and some national rail companies have placed new orders.

ÖBB, Austria’s national rail operator which runs about 20 services on its “Nightjet” network stretching from Budapest to Paris, will launch its new sleeper cars this year after a €720mn order with Siemens for 33 new train sets.

France’s SNCF, Finland’s VR Group and Norwegian rolling stock company Norske have also outlined plans to order or refurbish trains.

But Jon Worth, a railway commentator and campaigner, believes there is a “slew of new routes” that could be launched to meet the “enormous unmet potential” across Europe.

He said that only Europe’s state railway companies had the financial muscle to order new trains, but they were focused on growing daytime and high-speed services, while smaller entrants did not have the money to make a large order.

“The big companies that could do not want to and the small companies that want to can’t,” said Worth.

He estimated that it would take an order of between 200 and 300 carriages to make the cost per unit financially viable and called for greater co-ordination for a new order, either from a consortium of smaller participants, a national railway company or the EU.

In Brussels, the commission is working to promote rail travel as part of a drive to cut the bloc’s transport emissions and has estimated there are several untapped new routes that could provide effective competition with air travel.

It has offered technical assistance to help several pilot projects with the logistics of gaining access to the maze of tracks across Europe, but has given no specific funding for new carriages.

Yet passenger demand is so strong that it has outstripped supply even on ÖBB’s sprawling network, where there have been complaints from customers who assume the company’s website is broken because every single train is sold out.

“We get so many remarks that your system is down,” an ÖBB spokesperson said. “We are full, we are full, we are full.”