The Leeds Northern Railway (LNR), originally the Leeds and Thirsk Railway, was an English railway company that built and opened a line from Leeds to Stockton via Harrogate and Thirsk. In 1845 the Leeds and Thirsk Railway received permission for a line from Leeds to Thirsk, part of which opened in 1848, but problems building the Bramhope Tunnel delayed trains operating into Leeds until 1849. Today, sections of the former Leeds Northern Railway line form the Harrogate Line between Leeds and Harrogate, and the Northallerton to Stockton Line.