The Edinburgh and Dalkeith Railway used to run from Newington to Brunstane to the east of Edinburgh. Opened in 1831, the line was built to bring coal in to the city. It started to carry passengers as well, and became very popular. It was known as the Innocent Railway because the trains were pulled by horses. It was quickly overtaken by steam-powered railways though, and closed to passengers in 1847. It stopped carrying goods in 1968, and reopened as a foot and cycle path in the 1980s. The Innocent Railway Tunnel runs for 517m under Holyrood Park and is popular with grafitti and street artists. The entire length of the tunnel is covered with tags, murals, and slogans, and some of it is political.