The park behind Buckingham Palace that's hidden in plain sight

Green Park, one of the Royal Parks of London, is tucked away between Hyde Park and St. James's Park, across Constitution Hill. It was enclosed in the 16th century and was part of the estate of the Poulteney family. Initially not a burial ground for lepers, it later became a popular place for ballooning attempts and public firework displays. Handel's Music for the Royal Fireworks was composed for a fireworks celebration held in The Green Park in 1749, and it was a principal venue for the Grand Jubilee of 1814. Although a haven for highwaymen and thieves in the 18th and 19th centuries, it remains a popular spot for Londoners and tourists alike, a quiet retreat amidst the hustle and bustle of the city. Today, Green Park Underground station serves the park, accessible on the Piccadilly, Victoria, and Jubilee lines.

Sources: Wikipedia, OpenStreetMap, Wikidata, Wikimedia Commons