what is its structure?
It is composed of 14,233 lines that are divided into three "cantiche" (singular "cantica") – "Inferno" (Hell), "Purgatorio" (Purgatory), and "Paradiso" (Paradise) – each consisting of 33 cantos (Italian plural "canti").
Divine Comedy
The "Divine Comedy" is composed of 14,233 lines that are divided into three "cantiche" (singular "cantica") – "Inferno" (Hell), "Purgatorio" (Purgatory), and "Paradiso" (Paradise) – each consisting of 33 cantos (Italian plural "canti"). 
where did the battle of dyrrhachium take place? The battle was fought outside the city of Dyrrhachium, the major Byzantine stronghold in the western Balkans, and ended in a Norman victory. between whom did it take place? The Byzantine Empire, led by the Emperor Alexios I Komnenos , and the Normans of southern Italy under Robert Guiscard, Duke of Apulia and Calabria. when did the latter come into power? 1058 is he portrayed in literature? Yes, in the "Divine Comedy", Dante sees Guiscard's spirit in the Heaven of Mars can you tell me more about this work? The Divine Comedy is a long Italian narrative poem, begun c. 1308 and completed in 1320, a year before his death in 1321.
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Divine Comedy [SEP] Structure and story
Additionally, the verse scheme used, "terza rima", is hendecasyllabic (lines of eleven syllables), with the lines composing tercets according to the rhyme scheme "aba, bcb, cdc, ded, ...". The total number of syllables in each tercet is thus 33, the same as the number of cantos in each "cantica". Written in the first person, the poem tells of Dante's journey through the three realms of the dead, lasting from the night before Good Friday to the Wednesday after Easter in the spring of 1300. The Roman poet Virgil guides him through Hell and Purgatory; Beatrice, Dante's ideal woman, guides him through Heaven.