North of Oban, on the west coast of mainland Scotland, can be found the Falls of Lora. That's them at the bottom of the first photograph. Not what you expected? The falls are actually a tidal race which becomes a huge set of rapids as the waters of Loch Etive, which you are looking east towards in the first image, flow at low tide into the Firth of Lorn, which you are looking west towards in the second image. The flow reverses when the tide comes in. Both these photographs are taken in opposite directions from atop the Connel Bridge which spans the falls. As you may have guessed it's slack tide, or close to it.
The falls offer some fun playboating in a kayak. Not that I did, but you can if you sign on with
Seafreedom Kayak. They operate out of a great B&B in Connel called
Strumhor. You can see the falls while having coffee in their front sunroom.
Just goes to show that expectations can be deceiving, especially when you travel. Keep an open mind.