Tunnel, originally uploaded by Alec Saunders.

This photo is taken deep in the earth near Eganville Ontario, at the Bonnechere Caves. The Bonnechere River flows through the Lanark Highlands, west of Ottawa. Near Eganville, the river flows underground for a bit and has carved out an intricate set of limestone tunnels, which are pumped out every spring as a tourist attraction. The caves have deep striations in the wall due to the speed with which the water flows, and the rock is quite colourful.

It’s picturesque country, and the caverns are worth visiting if you’re out that way.

To see a few more photos, visit this Flickr slideshow.