historic county of north-central Wales, along the English border. Montgomeryshire is an area of wooded hills and valleys encircled by higher mountains, including Long Mountain in the east, Clifaesty Hill in the south, Plynlimon in the west, and the Berwyn mountains in the north. It extends to the Dovey estuary in the far west. Montgomeryshire lies entirely within the present county of Powys.
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