The world’s largest purported collection of international espionage-related artifacts plans to move about eight blocks south when the International Spy Museum relocates to L’Enfant Plaza in 2018.

Developer JBG Cos., owner of L’Enfant Plaza, announced a deal with the museum Wednesday after more than 18 months of negotiations.

JBG said construction was already underway on the new museum, a 140,000-square-foot space designed by London architects Rogers Stirk Harbour + Partners along with Hickok Cole of the District. It will be located in front of the Plaza’s glass atrium and feature a glass “veil” suspended in front of the new exhibition space.

In the meantime, the museum will continue to operate at 800 F St. NW.

Cleveland businessman Milton Maltz, creator of the museum, said that as a Navy veteran it was important to him that the museum grow its work explaining the history of intelligence-gathering.

“We consider it essential to ensuring the contributions of the dedicated men and women who serve in our intelligence agencies. They are recognized for the invaluable roles they’ve played in winning wars and protecting Americans at home and around the globe,” he said in a news release.

Leadership at the museum, which is a nonprofit, began considering L’Enfant Plaza in 2014 after shelving a long-planned move to the Carnegie Building. The deal was enabled by a commitment from D.C. Mayor Muriel E. Bowser (D) to help finance the project using $50 million in tax-exempt bond financing, money the museum will have to pay back but at a lower cost than without District backing.

“The International Spy Museum has long been a destination for residents and visitors, finding innovative ways to keep us connected with our past,” Bowser said in the release. “The new Spy Museum will be a welcome addition to Southwest as we continue to attract businesses and expand economic opportunity.”

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