As Europe endures another summer of extreme heat, prison officials, inmates and rights advocates say soaring temperatures are pushing overcrowded and ageing correctional facilities to the breaking point, exposing long-standing structural problems that governments have struggled to address.

When temperatures climbed above 37 degrees Celsius (98.6 degrees Celsius) outside, a 29-year-old French inmate named Manu sat inside his cell at Orleans-Saran prison with wet towels draped over the window bars, trying to keep the heat at bay while describing the stifling conditions to a visiting politician.

Most days, he said, the only way to cope was to stay on his bed and avoid unnecessary movement.

"You have to deal with it mentally," Manu said from the prison, which opened in 2014 and is among France's newest correctional facilities.

Reuters accompanied the July prison visit and interviewed more than 40 people in France, Italy and Belgium, including inmates, prison directors, doctors, union representatives and prison reform advocates.

Many painted a similar picture of prison systems buckling under record summer temperatures, with overcrowding and outdated infrastructure leaving thousands of inmates trapped in dangerously hot conditions.

Heat reveals deeper problems

France's chief prison inspector, Dominique Simonnot, said her office was overwhelmed with complaints from prisoners during June's intense heatwave, forcing the independent watchdog to hire an additional employee to handle the surge.

"Imagine, we are suffocating in our flats, and they are three to four people in one nine-square-meter cell, in a building that is not adapted, not air-conditioned, old and where the heat is overwhelming," Simonnot said.

The dangers became apparent in Limoges, south of Orleans, where an inmate reportedly collapsed during the early hours of July 8 after becoming overwhelmed by the heat.

His lawyer, Charly Salkazanov, said the prisoner lost consciousness while getting up to use the bathroom, fell and suffered a head injury.

A prison officers' union representative disputed that account, saying the inmate slipped while climbing toward a window in search of cooler air. Reuters was unable to independently verify either version.

Salkazanov said he had requested the prisoner's medical records and warned that similar incidents would continue unless authorities took meaningful action.

"This kind of thing will happen repeatedly until the authorities wake up," he said.

The Bordeaux regional prison authority, which oversees Limoges prison, declined to comment on the specific case but said inmates were being given greater access to showers and drinking water while also being allowed to purchase fans and sunscreen.

France's Justice Ministry said similar measures had been implemented nationwide, including additional showers, increased water supplies and sunscreen distribution.

Justice Ministry spokesperson Sacha Straub-Kahn acknowledged that emergency measures alone were insufficient, saying reducing overcrowding remained the long-term solution.

"In the long and medium term we need to simply try and fight against prison overcrowding, which accentuates the difficulties of the heatwave," he said.

Overcrowding stretches prison systems

France's prison occupancy rate stood at 141.3% on July 1, according to government figures.

Italy faced similar pressure, with prison rights organization Antigone reporting an occupancy rate of 139.7% in late July, while Belgium's prison monitoring council said the country's prisons were operating at 121% capacity in August.

The figures highlight a common challenge across Western Europe, where prison populations have outgrown facilities that were never designed to withstand prolonged periods of extreme heat.

Italy pushes for reforms

Concern over prison conditions prompted a coalition of Italian prison rights groups to organize coordinated visits to 34 prisons on July 14 in an effort to draw attention to what activists described as inhumane living conditions.

Patrizio Gonnella, president of Antigone, criticized the lack of basic cooling measures.

"It's absurd that there are no refrigerators in cells, it's absurd that there aren't fans everywhere, it's absurd that inmates have to spend 20 hours a day in their cells," he said outside Rome's Regina Coeli prison.

Italy's Justice Ministry has allocated 800,000 euros ($923,280) for prisons to purchase fans and refrigerators and has pledged to create an additional 10,000 prison spaces by the end of the year. Ministry data, however, show none of those new places have yet been completed.

Italian lawmakers have also approved legislation allowing thousands of inmates with drug or alcohol addictions to serve their sentences at home while participating in rehabilitation programs, a move aimed at easing overcrowding.

In Cosenza, authorities agreed in June to remove plexiglass barriers from prison windows after officials concluded the screens, originally installed to prevent contraband deliveries by drones, severely restricted airflow inside cells.

Belgian prisons feel the strain

Belgium has also extended heatwave protocols after prison officials reported worsening conditions.

Justice Minister Annelies Verlinden said inmates had been given increased access to drinking water and showers, while prison administrators instructed facilities to maintain heat mitigation measures through September.

Directors of two of Belgium's oldest prisons, in Ghent and Merksplas, said rising temperatures were fueling more confrontations between inmates and staff.

Ghent prison director Pieter Van Caeneghem said his facility was housing 447 inmates despite having space for only 260.

"All the problems linked to overcrowding are twice or ten times more difficult when there is a heatwave," he said.

Merksplas prison director Serge Rooman said he began relaxing some security procedures during heatwaves three years ago by allowing cell windows to remain open overnight and opening prison doors to improve ventilation. Those temporary measures have since been incorporated into official guidance.

Still, he said, the underlying issue remains the condition of Europe's ageing prison infrastructure.

"The fundamental problems are the buildings," Rooman said, pointing to poor ventilation and outdated single-pane windows.

He argued that prison construction rarely becomes a political priority despite worsening conditions.

"Nobody wins votes by saying they are going to build or renovate prisons because it's too hot in the summer," he said. "But in Belgium, the punishment is the deprivation of liberty, not exposure to inhuman conditions."