Wellington Arch, also known as Constitution Arch or (originally) the Green Park Arch, is a triumphal arch located to the south of Hyde Park in central London and at the western corner of Green Park (although it is now isolated on a traffic island).

Transferred to the ownership of English Heritage in 1999, it is open to the public and contains three floors of exhibits detailing the history of the arch and some of its uses. Visitors can also step onto terraces on both sides of the top of the arch, which give views of the surrounding area.