Its quite a hill so its easy to see why they needed to build the tunnel.
Here we are at the southern portal as a boat emerges from its half hour trip underground.
Hopefully next year we'll be taking Herbie through here on our summer cruise.
Herbie now boasts a beautiful name brass made by Rick. We're not quite sure where best to hang it yet, but here it is alongside our quirky pressure gauge quartz clock.
We'll be back on the water next week for a few days with our friends Jan and Steven after their son's wedding at the weekend.