Next to Holyrood Park, near the foot of Arthur’s Seat lies a pathway that runs partially underground. It was once Edinburgh’s first railway line, where horse-drawn trams started bringing coal to Edinburgh from the mines further south. It started operating in 1831 as the Edinburgh & Dalkieth Railway Line, designed by Scottish civil engineer James Jardine.
A plaque at the entrance ascribes the name ”Innocent Railway” came from the horse-drawn trams being safer and more sophisticated than steam engines. Some sources attribute the name to the fact that there were no casualties while building the railway.
It was the first underground railway passage in the United Kingdom, stretching for an estimated nine miles. The railway was popular with the locals, and became more popular as a passenger line than as coal transport. In 1845 the railway switched to steam-operated trains.
After the coal depot at St. Leonard’s shut down, the railway ceased operation in 1963. In 1981 it was reopened for use as a pedestrian and cycle path, one of many in Edinburgh. It’s also part of the U.K. National Cycle Network’s Route 1.
The entrance can be tricky to locate, unless you know what you are looking for. Once you locate the entrance, the tree-lined trail can take you from the south side of the city, around the bird sanctuary of Duddinston Loch near Duddingston Village before continuing on southward.