A summary life of the poet

The "Purgatorio", perhaps the most artistically perfect of the three canticles, owes less to the beauty of the separate episodes. Dante's conception of purgatory as a lofty mountain, rising out of the ocean in the southern hemisphere, and leading up to the Garden of Eden, the necessary preparation for winning back the earthly paradise, and with it all the prerogatives lost by man at the fall of Adam, seems peculiar to him; nor do we find elsewhere the purifying process carried on beneath the sun and stars, with the beauty of transfigured nature only eclipsed by the splendour of the angelic custodians of the seven terraces. The meeting with Beatrice on the banks of Lethe, with Dante's personal confession of an unworthy past, completes the story of the "Vita Nuova" after the bitter experiences and disillusions of a lifetime.

The above is from a brief vita taken from the Catholic Encyclopedia on the New Advent site. The entire text is riddled with hyperlinks which go to richly hyperlinked articles in turn (like this one on Purgatory). One could easily get lost in this selva oscura for quite some time.