After a long fight, Copenhagen’s environmentalists are breathing a sigh of relief.

For the past few years, a sweeping, wildlife-rich grassland called Amager Faelled, just south of the city center, had been under threat of potentially damaging (if limited) development. Even exploring the suitability for buildings last month caused upset, when tests to the proposed construction site caused the deaths of some rare animals. Then, abruptly on Wednesday, Copenhagen’s Lord Mayor Frank Jensen announced h…