Everard Richard Calthrop (3 March 1857 – 30 March 1927) was a British railway engineer and inventor. Calthrop was a notable promoter and builder of narrow-gauge railways, especially of 2 ft 6 in (762 mm) narrow gauge, and was especially prominent in India. His most notable achievement was the Barsi Light Railway, but he is best known in his home country for the Leek and Manifold Valley Light Railway. Calthrop has been described as a "railway genius". Later in life he took an interest in aviation, patenting some early designs for parachutes.