The colours of this underground creek really drew me in.
We came across this uniquely-coloured body of water at Headquarter's Conversation Area.
(For a while in my youth, I thought it an odd name, thinking someone who had the name "Headquarters" had this place named after them. Of course, now I know it's only named this for being the location of the headquarters of the Saugeen Conservation Authority.)
Until this near sea-blue location, the creek runs above ground, then heads underground for a long while, eventually joining the Saugeen river system. This is also a rather sulferous water source as well, so there's a bit of a smell to it.
This would be the first spot I had ever seen a water source head underground, or dissapear in the middle of a forest, and also the first time I had seen colours like these naturally occuring. It is similar to sea-green, but slightly more silvery. Not unlike a greenish pool.