travel through some sort of tunnel that is underwater (by car, walk) etc

I’ve been in the tunnel between England and France as well as the Detroit Tunnel connecting Detroit to Windsor, Canada. 3 years ago

Drove a car through a tunnel on the east coast of US. 4 years ago

I’ve been through a few. I went through a swim through one of which was a man made swim through (sunken irrigation pipe) and another was a place in Cancun where the coral had formed a little bridge that only one person could fit through at a time. Good stuff. 5 years ago

it didn’t even feel like it was underwater, it felt the same as all the other tunnels in sydney. it’s just not the same as going over the sydney harbour bridge though. 5 years ago