A railway line from Avonmouth to Clifton was built in the mid 1850s. Initially operated by a private company, it was taken over by the Great Western/Midland in 1871. At its southern end, near the terminus station of Hotwells, two short tunnels were constructed.The line closed in 1921.
The northerly tunnel was known as Portway number 2 and was 175 yards long. Bridge Valley Road was later built over the tunnel. In World War II, this tunnel was converted into a public air-raid shelter, complete with toilets. Post war, the tunnel was used for a time by a local gun club. Much of the tunnel was filled in stability works to Bridge Valley Road around 2010.