Original sentence: The Caucasus region  is geographically a part of Asia (thus the Persian name Qafqâz), but historically and culturally it is often seen as a part of Europe
Edited sentence: Sometimes it is historically and culturally seen as a part of Europe.The Caucasus region south of the Caucasus Mountains crest is geographically a part of Asia (thus the Persian name Qafqâz), and geographically a part of Europe north of the Caucasus Mountains crest