Kettleness Tunnel is lucky to have ever existed. The engineer who originally developed the Whitby Redcar & Middlesbrough Union Railway didn't cover himself in glory when he plotted a course beneath North Yorkshire's unstable cliffs. Fortunately financial issues brought a hiatus mid-project, during which time parts of the route crumbled away. Common sense prevailed when the North Eastern Railway took over, pushing the line further inland through two tunnels, one of which was Kettleness.
K-Burn has been busy for us this month with two structures from north of the border. Rodney Street Tunnel is a cut-and-cover product in central Edinburgh which opened for business in the age of horse-drawn trains. Today's traffic is also muscle-powered: walkers and cyclists use it as a commuting route. Across the Forth, he also visits Glenfarg Viaduct on the former main line to Perth which has recently been the focus of remedial works. If only the trees had been cut back so we could see it.
July's final offering is the fabulous Mountsorrel bridge which features one of the finest brick spans in the country. Opened in 1860 on a quarry line - also horse-drawn, the structure is exquisitely designed with embellishments at every turn. Despite the Grade II listing, it is looking a little tired though as a result of ill-considered repair work resulting in localised deterioration of its brickwork.
You'll see that the Disused Tunnels Database has been extensively updated this month with a raft of revisions and a few new entries. Just when you think you've unearthed all the tunnels going, others emerge to catch your eye.
And finally, if, like me, you're a dinosaur and look back with dewy eyes on those days - pre-health 'n' safety - when we were allowed to have adventures, you'll love this picture. Four lads (and a fifth holding his camera) bedecked in wellies and short trousers, with smiles as wide as the portal they're in front of. Feel the nostalgia; relish the characters. I can't stop smiling!