Last autumn we went to the largest waterfall in Europe: the Rheinfalls near Schaffhausen. It’s over 150 metres wide, 23 metres tall, and is apparently anywhere between 14,000 to 17,000 years old. There’s a rock right in the middle of the falls, which is accessible by ferry. You can climb right up to the top of the rock and enjoy the view, which many visitors do. I chose not to, because the weather wasn’t too great at the time, and I have a deep aversion towards narrow, spiral staircases. We did, however walk to the platform which juts out from the middle/underneath the falls, and experience the gushing water up close. It’s worth a visit if you’re in the area and you have time on your hands.
Oh and according to our good friend, Wikipedia, fish can’t climb the falls; but eels can.