There is a push in Yorkshire, UK to turn the abandoned Queensbury rail line into England’s longest cycle tunnel. The 1.4-mile line was closed in 1956 to rail travel, and as indicated in the photo, is in need of some serious help. The local Department for Transport (DfT) wants to spend about $4M USD to fill in the tunnel permanently, but local stakeholders want to see the cycle tunnel made a reality.
One report claims the cost of the cycle tunnel would be in the neighborhood of $47M USD, while another number quoted by the Queensbury Tunnel Society is $5.8M USD…quite a range of costs. A cycle tunnel would likely require lining with reinforced shotcrete and the addition of ventilation shafts and other infrastructure.
Source: New push to make England’s longest cycle tunnel a reality | UK news | The Guardian via AEG News