According to the answer of @what to the question Pronunciation of “lernst” there are 3 different ways to pronounce the alphabet r
in German:
voiced uvular fricative [ʁ] (splattne's sample)
uvular trill [R]
alveolar trill [r]
(Regarding "splattne's sample" see his answer.)
My question is regarding the uvular trill. Which region is this pronunciation associated with? Is this the pronunciation in Hochdeutsch? And which of these is the most common in Germany?