Medals for soldiers running a shadow Boston Marathon await runners at a U.S. army base in Kuwait in 2017. Photo by Sgt. Kimberly Browne | USARCENT Public Affairs

The previously postponed 2020 Boston Marathon has been canceled and will not be held on the Sept. 14 date officials originally targeted when they called off the traditional April running of the 26.2-mile road race due to concerns about the coronavirus, Boston Mayor Marty Walsh announced Thursday.

Earlier this year, city leaders and the Boston Athletic Association agreed to delay the race for the first time in its 124-year history because of the enormous health risks posed by bringing together thousands of runners and even more spectators in close proximity.

They hoped to create a new state holiday on Sept. 14 to recreate the marathon experience in the fall, but Walsh said Thursday that hosting the major event in less than four months has become “less and less plausible.”

“The traditional one-day running of the 124th running of the Boston Marathon is not feasible this year for public health reasons,” Walsh said at a Thursday press conference. “There’s no way to hold this usual race format without bringing large numbers of people into close proximity.”

BAA officials plan to issue refunds to any participants who had registered for the race, and they will also organize a “virtual marathon” in an attempt to fill the void that will exist until the 2021 iteration of the race.

The move could create significant problems for Back Bay hoteliers and retailers who typically see a large surge in business on Marathon Weekend.