Was Dante’s Mnt. Purgatory any kind of inspiration for Tolkien’s Minas Tirith? I doubt it, but aside from both structures involving seven terraces or levels (profound, I know), the illustration of Purgatory from my copy of the Penguin Portable Dante always makes me think of Peter Jackson’s representation of Gondor’s white-walled city (which, speaking of things medieval, I understand to have been modeled on Mont Saint-Michel, also below).
The Flame Imperishable 