'The best lens for landscapes is a wide angle', how many times has this advice been given? I give it myself and on the whole I agree with this, but this is not a hard fact. Any lens is good for landscapes and a medium to long telephoto lens is also very useful and I use my 55-200mm (80-300mm equivalent) on almost every photography trip.
A telephoto lens isolates elements of the landscape and it also compresses the perspective, bringing items in the composition closer together. For example in the shot at the top of this page of Barns Ness lighthouse, Bass Rock can be seen to the left of the lighthouse. In this shot it looks like The Bass is just beyond the headland when in fact it is a few miles away out in the Firth of Forth.
This 'stacking' of the different elements is highlighted when the light is slightly behind the subject as in the shot below of Lismore Lighthouse in the Sound of Mull. The lighthouse is dark, the shoreline in the middle distance is lighter and the hills on the Isle of Mull is lighter still. The three elements are miles apart but in this image taken on a Nikon D90 and Sigma 50-500mm (at the 500mm end of the zoom) compresses the perspective.
Some more examples of using a telephoto for landscape images are below and I always have my 56mm and 55-200mm lenses available when out shooting.
All images taken on a Fujinon 55-200mm f3.5/4.8 with the exception of Lismore Lighthouse