This is an excuse to show you a really good tunnel

There were so many possible titles and thumbnails for this video. "Does attaching a camera to your car cost money?" "It's a reverse wind tunnel." "Testing like this used to be impossible." In the end, I just decided I wanted to show you a good tunnel.

Tom somehow manages to continue his trend of train videos despite not having a single train in sight

You don't need an excuse to show us really good tunnels

Cool to see a professional in the automotive industry refer to it as an "Austin Powers turn".

I really like that the solution to the problem of "there are bats in the tunnel" was "build a bat hotel".

3mm in 2.7 km? That's an absurd level of precision even for today, much less Victorian England. What the hell?

I love that last sentence "this is the closest I´ve gotten to science in a long time". I´m especially remembering the "toaster numbers don´t mean minutes" and the "I want to destroy my fingerprints with pineapple-based torture" videos as examples of Tom Scott ´doing science´.

I love how the multi-point turn has become universally recognized as the 'Austin Powers' turn.

I liked that Tom used the fact that he uses different cameras as a way to thrown some science into the video.

Gonna be honest Tom, I am mostly upset that this video isnt about the Bat Hotel

Loved the editing on that cut from "we don't want to see the cameraman in the back - because he isn't there." Like a magic trick but not exactly secret as to how it works haha

I used to work there. Jon is a great guy and a great boss. I’ve got a lot of respect for what he’s achieved and for how he’s running that place.

3mm deviation off the laser is absolutely crazy to me. How did they do that?

This indeed is a good tunnel

As someone who used to work in notoriously more active tunnels, l can say that the procedure for turning around the wrecker/fire trucks was full lock turn until you hit the wall, full lock the other way until you hit the other, then full lock again into the wall once more if you set yourself up well and twice more if you didn't. The trucks were build with this procedure in mind, the difference those last few inches made was astounding

In case anyone is confused by the tunnel being "flat," yet having a gradient: "Flat" is not the same as "level." A level line is a curved line (constant distance from Earth's center of gravity). This tunnel is instead "flat," meaning straight, not curved. It has gradient, because one end is higher in elevation than the other (probably to facilitate drainage), and the elevation difference between the ends would have to exceed the difference of the middle from level. In the absence of gradient, all water that seeps into a flat tunnel would drain to the middle, because that's the point lowest from level.

I love how Jon Paton had to remind us that the surface of the earth is curved, just in case a certain group of people unironically cite the laser light as proof the earth is flat...

Excellent reuse of infrastructure. I feel there are a lot of old abandoned things that could be reused. It’s just that the people that could use it don’t know it exists.

Tom's obsession with tunnels or just a big hole underground is comparable to the obsession of Sam from Wendover to airplane/logistics.

Adam Something is correct, even when it comes to designing cars, railways are the answer. Another weird, entertaining and informative video from Tom and his crew. Now I want to see the same experiments being run with different breeds of dogs with their head out of the window.