PALM BEACH, Fla. — Hurricane Irma is likely to test President Donald Trump's longtime boast that his Mar-a-Lago mansion can withstand any storm.

If history is any guide, the smart money this weekend will be on the house.

Strikes by four major hurricanes have done little damage to Mar-a-Lago in the 90 years since cereal heiress Marjorie Merriweather Post and her second husband, financier E.F. Hutton, built the 126-room, 62,500-square foot (5,800-square meter) mansion. It cost them $5 million — the equivalent of almost $70 million today.

The 3-acre (1.2 hectare) Palm Beach estate is quite exposed to tropical weather, bisecting a narrow barrier island, flanked by the Intracoastal Waterway and the Atlantic Ocean. But the mansion's walls are 3-feet (1 meter) thick, anchored by steel and concrete beams embedded into coral rock.

"It's the safest place in the world for a hurricane," said Anthony Senecal, Trump's longtime butler and Mar-a-Lago's unofficial historian, in an interview with The Associated Press last year. "That house ain't going nowhere. That house has never been seriously damaged. That construction, stop and think about it. There were 300 guys that worked on the outside of that building."

On Friday, shutters could be seen covering some of the mansion's windows.

"Our teams at our four properties in Florida are taking all of the proper precautions and are following local and Florida State Advisories very closely to help ensure that everyone is kept safe and secure," said Amanda Miller, a Trump Organization spokeswoman.

Trump's three private clubs in Florida — Mar-a-Lago and golf courses in Palm Beach and Jupiter — have been closed, and guests at the Trump National Doral golf course are being encouraged to relocate outside the storm's reach, her statement said.

Jeff Masters, director of the Weather Underground forecasting service, said Thursday that the biggest threat to Mar-a-Lago won't be Irma's winds, which could top 140 mph (225 kph) when it reaches Palm Beach. Instead, it will be storm surge, which he said could reach 8 feet (2.4 meters) in a worst-case scenario. An interactive map by Climate Central shows that a more likely 6-foot (1.8-meter) sea rise would put some of the property's low-lying areas at peril. An 8-foot surge could cause some water damage to the main buildings.

Trump bought the property in 1985, when it was in disrepair, for $10 million, and spent millions refurbishing it before turning it into a club in 1995. The property now boasts 58 bedrooms, 33 bathrooms, a 20,000-square-foot ballroom, tennis and croquet courts and three bomb shelters.

The Trump family business doubled the initiation fee to $200,000 once it became clear that Mar-a-Lago would become the unofficial Winter White House, and the president has spent seven weekends at the resort since his inauguration, mingling with the club's 500 members, who pay $14,000 in annual dues to belong.

An AP investigation last year showed Trump received a $17 million insurance payment for Mar-a-Lago damage in 2005 after hurricanes Frances, Jeanne and Wilma hit in two years, but he said in an unrelated lawsuit deposition in 2007 that he didn't know how much was spent on repairs. He conceded to pocketing some of the money.

Senecal told the AP the roof lost some tiles and some trees were flattened. Town of Palm Beach records showed no permits were issued for major repairs during that period.

The first major storm to hit Mar-a-Lago was the 1928 Okeechobee hurricane, which made landfall nearby with 145 mph winds. Just 45 miles (72 kilometers) west, dikes surrounding Lake Okeechobee failed and at least 2,500 people drowned, mostly farmworkers and their families. More than 1,700 buildings near Mar-a-Lago were destroyed. According to the Palm Beach Post, Mar-a-Lago reported damage to a large Roman-style window.