CADDY LAKE, Man. - Every summer, outdoor enthusiasts flock to a set of cavelike tunnels just west of the Ontario-Manitoba boundary. The Caddy Lake tunnels were created more than a century ago as part of railway construction.

Workers blasted through solid Canadian Shield rock to let water flow and reduce the chance of flooded tracks. In the ensuing decades, people have been able to travel by canoe, kayak or small motorboat under and through the jagged rock. For a moment, the light at either end of the tunnels can almost disappear, creating a spooky atmosphere made eerier by small birds swooping just above your head.

“I still think it’s pretty special how there are these doorways to wilderness there,” Tony Lavilla, who owns property in the area, said this week. “People we take up there are just blown away.” There is a campground, a public launch area and two resorts with rental watercraft on Caddy Lake, where most people start the tunnel tour.

The lake is wide and open to the wind until you approach the first tunnel — a high-ceiling, narrow passage with a bend about halfway through. You can reach out and touch the rough, uneven rock walls that jut out sideways. It’s three kilometres from the start — roughly 45 minutes each way if you’re paddling in good weather.

That tunnel spills out into South Cross Lake and more open water. Getting to the second tunnel is a more arduous affair. The journey is an additional six kilometres or 90 minutes of paddling each way a.