There are several hiking trails leading to the Triberg waterfalls. Near as I could figure out, you might be able to walk part of them without paying the admission price for the falls.
That means of course that you don’t get to see the falls, but sometimes just being in a forest is enough. And though you may not see the falls, you can hear them.
We went on the Nature trail, which was pretty much as you would expect. On a hot day I would have preferred a trail with fewer roots to trip over and perhaps a little less up and down. Still, it was a pleasant walk in the forest, and we did see some red squirrels, which appear to be the dominant animal life form in the area. I never did figure out what the “culture” part was of the Culture trail, unless it was the zip-lining – but it didn’t really matter since we were using the trail primarily as the route to get back to the centre of town where we parked our car.