The City of Glasgow Union Railway - City Union Line, also known as the Tron Line, was a railway company founded in Glasgow, Scotland, in 1864 to build a line connecting the railway systems north and south of the River Clyde, and to build a central passenger terminus and a general goods depot for the city. The through line, running from south-west to north-east across the city, opened in 1870–1, and the passenger terminal was St Enoch railway station, opened in 1876. The railway bridge across the Clyde was the first in the city.