About 40 Iowa National Guard members last year were bused about 23 miles from an airplane refueling stop in Scotland to room overnight at President Donald Trump’s Turnberry resort.

It’s one of at least four separate military stays at the resort that are being investigated by the House Oversight Committee to determine whether Trump improperly gained from U.S. military lodging at his properties.

The Iowa National Guard’s Sept. 21, 2018, stop was part of the group’s second trip to Kosovo for a training and partnership mission with the southeastern European country.

The group — along with a Des Moines Register reporter and photographer — landed at Glasgow Prestwick Airport. They were transported by bus about 23 miles to the Trump Turnberry Scotland, a luxury resort that markets itself as having one of the top golf courses in the world with views of the Ayrshire Coastline.

The two Register journalists spent six days with the military group, mostly in Kosovo, where they chronicled the Guard's efforts to help train the Kosovo military. In Scotland, the Des Moines Register paid for two rooms at the Trump property at a cost of about $150 each. Guest rooms listed on the resort's site Wednesday cost between $356 and $702.

Air Force spokeswoman Ann Stefanek said in a statement to USA TODAY that Glasgow Prestwick Airport has been used as a stopover location since 2015 because of its 24-hour operations, parking availability and fuel contracts with the Department of Defense.

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U.S. military spending at Glasgow Prestwick Airport appears to have increased substantially since Trump took office, with $11 million in fuel being purchased since October 2017, according to a letter the congressional panel sent to the Pentagon in June.

The financially struggling airport — important to the golf course's financial success — provided “cut-rate rooms” and free rounds of golf at Turnberry for U.S. military members, the letter says in citing a report from the Guardian.

“Given the President’s continued financial stake in his Scotland golf courses, these reports raise questions about the President’s potential receipt of U.S. or foreign government emoluments in violation of the U.S. Constitution and raise other serious conflict of interest concerns,” U.S. Rep. Elijah Cummings, a Maryland Democrat and chairman of the House Committee on Oversight and Reform, wrote in a June 23 records request to the U.S. Department of Defense.

The rates paid by the military were below the $166 per diem rate, said Col. Michael Wunn, former director of the Iowa-Kosovo partnership who was part of the trip last year. No closer hotel was able to accommodate the group within the government's rate limits, Wunn said.

Wunn said decisions about where to land to refuel and where to stay are part of complex review conducted through the Defense Travel System, sometimes referenced as the "Pentagon’s in-house travel agent."

“Our folks work through the process, and they’re making decisions based on what they need to do to support the mission,” Wunn said. “I’m confident that’s what guided those decisions as far as stopover and where they stayed and all those sorts of things.”

The Iowa National Guard group will leave Sunday for a third training trip to Kosovo, returning Sept. 21. The group’s refueling stop this year is in Germany; they will stay in lodging at Spangdahlem Air Base, Wunn said.

At least three other military stays at Turnberry are the subject of a congressional investigation, according to a Politico story published this week. In total, more than 60 service members stayed at the resort, Politico reported.

Jason Clayworth is an investigative reporter for the Register. Reach him at jclayworth@dmreg.com or 515-699-7058.

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