I can't speak for the other two countries but you'd have some difficulty finding beautiful places in Britain that are not well-known, because there are any number of beautiful places here, but they are all easy to reach.
Well-publicised too, including by glossy-magazine journalists paid to find "hidden gems" and "secret places" in order to ensure they are no longer "hidden" or "secret" (not that they ever were, of course).
@James57 Yes, indeed. In my teens I would explore the countryisde on foot, not usually off the roads though, equipped with no more than a packed lunch and an One-inch Ordnance Survey map. The "Explorer" series had not yet started.
A friend told me he was once asked by a group of walkers in the Three Peaks area, if he knew of any good walking guide-books to the area.
The Explorer range may be new but in my childhood, they were available as the two and a half inch or 1:25000 scale maps, covering a much smaller area, more convenient for walking. It was my father, a scout leader, who gave me my love of maps. A map is better than a good book. For a place to be beautiful, you don't need a view. Some of the best places are hidden forest glades in a deep valley with a stream running over boulders, sunlight hinting through the trees, damp moss on the ground. Truly magical.
@James57 That is a lovely place indeed, and I agree completely that there are more than sweeping vistas.
I love looking at maps anyway, and I have an atlas to help me understand events in the News better.
Maths was always about my weakest subject at school, and I am not much better now, but I did find basic three-dimensional [(x,y,z)] co-ordinate geometry straightforwards because I could see it as an abstract version of the NGR and altitude markings on maps.