The rail line between Canberra & Cooma was closed to passenger trains in September 1988 after the bridge over Numeralla Creek was deemed unsafe, freight services along this line ceased in May 1989.
The 49km section between Queanbeyan and Michelago was reopened in April 1993 for heritage tourist operation however this was suspended in the beginning of 2007 due to storm damage.
The rail line had stops at Royalla, Williamsdale, Michelago, Colinton, Bredbo, Billilingra, Chakola, Bunyan and Cooma, with bridges crossing Ingalara Creek, Bredbo & Numeralla Rivers and a tunnel under the hill at Colinton.
Colinton Tunnel is a 161m single tracked tunnel that was opened on 31 May 1889 and closed on 3 March 1990. The tunnel was built with 500,000 bricks, made locally at Bredbo. The tunnel cuts through granite and bluestone quartz.
Starting point is S35 51.802 E149 09.244 (near “The Forgotten Series – Bridge I” cache.)
To access this cache you will need to walk 5 km’s there & 5km’s back, along the disused railway line. (You will not need to venture into private property.) You will be rewarded with some beautiful sites along the nice flat easy walk.
If you are unable to walk this distance, there is a shorter route along the rail at the southern end of the tunnel at S35 51.810 E149 09.282. Please note that you will need to contact ‘Bush Heritage Australia on 1300 628 873’, and politely request access through the front gate of the Scottsdale Reserve driveway, so you can walk along the rail line to visit the historic Colinton Railway Tunnel. (You will not need to access anywhere outside of the roadway or railway.)