SAN JUAN, Puerto Rico (AP) — Stained glass windows from the 16th century are broken. Porch railings from the 1700s are missing. Brick walls crumble inside the hall where Spain ceded Puerto Rico to the US.

Puerto Rico’s prized historic buildings are falling apart as a debt crisis and enduring economic recession have slashed public and private funding for maintenance, repairs and restoration. Tourists are increasingly banned from visiting once-popular sites now in dangerous disrepair.

Overall, nearly 40 key buildings in the metropolitan area are in danger of being lost, according to Andy Rivera, an architect who founded the Puerto Rico Historic Building Drawing Society.

“It’s a shame these things are deteriorating, and nobody is calling attention to it,” he said.

The majority of these buildings are in the historic part of Puerto Rico’s capital known as Old San Juan, founded in 1521 and governed by Spanish explorer Juan Ponce de Leon. It is a top tourist attraction with its blue cobblestone streets, colourful homes and expansive ocean views.

But dozens of historic buildings there are decaying. The exact number is unknown because the government hasn’t carried out structural evaluations of them in more than five years, said Carmen Marla Lopez, director of the historical heritage programme at the Institute of Puerto Rican Culture.

“Given our fiscal situation, a lot of people and even the government itself do not have enough money to intervene in all the properties it would like to,” she said.

Many of the buildings are owned by the government of the US territory, whose maintenance budgets have been cut along with most other spending at a moment when officials are trying to restructure a portion of its

US$73-billion public debt.

Private and other non-governmental maintenance budgets also have been squeezed by a severe, long-lasting recession that has been aggravated by government cutbacks in jobs, pensions and general spending.

As a result, authorities have closed several buildings and museums because they have decayed to the point where they pose a danger to the public, Rivera said.

Among them is the bell tower of the Cathedral of San Juan Bautista in Old San Juan. Worshippers and tourists can visit the rest of the 16th century church, best known for housing the remains of Ponce de Leon. Other attractions also have been damaged: Church officials were forced to remove several broken stained glass windows and a huge, antique organ because it was filled with termites. The church’s walls are crumbling in many places and mold is clearly visible.

A large sign at the cathedral’s entrance asks visitors to leave a donation to help finance the reconstruction project, although the extent of the damage and cost of the project is unclear. The Rev Benjamin Perez, who helps oversee the project, did not return messages for comment.

Also shuttered for safety reasons are an apothecary museum in a building from the 1700s and a historic theatre, the Home of the Two Forecourts, built in the mid-1700s.

“The balcony in the interior patio was going to collapse at any minute,” Lopez said.

Safety concerns led to closure of the hall where Spain signed a historic deal turning Puerto Rico over to the US government in 1898 after the Spanish-American War.

One big concern is that the longer a building remains shuttered, the more it costs to restore, especially where a tropical climate speeds deterioration.

That is one of the reasons officials have struggled to reopen the National Gallery, a renowned seaside museum that housed the largest collection of Puerto Rican paintings from the 1700s onward, as well as antique furniture and military artefacts. It closed in November 2013 amid concerns over restoration permits, and projected costs keep rising as budgets keep shrinking.

“It’s going to take a lot of work to reopen because it’s been closed for several years,” Lopez said. “We’re evaluating its current condition.”

When the agency said it did not have US$35,000 to renovate a historic fort on the nearby island of Vieques, the local community and sponsors helped raise the money needed. Lopez said she envisions similar arrangements in the future.

“We have to look for other ways given the economic crisis so we don’t lose these properties,” she said. “There are certainly serious concerns that these properties cannot be maintained.”

Puerto Rico’s government in some cases has opted to sell or lease historic buildings to individuals or non-profit groups in hopes they can finance restoration. A private university is remodelling a building that was once an iconic movie theatre in Old San Juan.

Rivera, the architect, said he understands the government cannot do it alone, but stressed there are other options.

“Lack of money is no excuse,” he said. “Conservation is important so that the children of your children know where they came from.”