In Dante's vision of the afterlife, hell is a cone-shaped funnel located directly underneath the city of Jerusalem, and was created when Lucifer, the fallen angel, was cast out of heaven for his rebellion against God. Hell is divided into nine cerchi or circles, and in each circle a particular sin or vice is punished.
First Circle (Limbo): Virtuous Pagans born before the time of Christ; Unbaptized Children
Second Circle: The Lustful
Third Circle: The Gluttonous
Fourth Circle: The Avaricious and Prodigal
Fifth Circle: The Wrathful
Sixth Circle: The Heretics
Seventh Circle: The Violent
Eighth Circle: The Fraudulent
Ninth Circle: The Traitors
Angels who refused to take sides with either Lucifer or God during the rebellion are doomed to spend eternity in a place between the Gates of Hell and the first circle called “Ante-Hell”. The upper region of hell which includes the first five circles is reserved for what Dante considers less serious sins or sins of incontenenza (lust, gluttony, greed, and wrath). These sins are committed out of the inability to control one's passions. Sins of malizia,on the other hand, are deliberately and willfully committed, and are therefore punished in the lower region of hell (heresy, violence, fraud, and treachery). Although all in hell are equally damned, the lower region is reserved for the most wicked of souls because it is furthest from God.
Dinanzi a me non fuor cose create
se non eterne, e io etterno duro.
Lasciate ogni speranza, voi ch'intrate. (Inf. III. 7-9)
According to Dante's vision of the afterlife, souls that are not damned, yet not worthy of heaven, must first enter Purgatory. Purgatory is a place of redemption and therefore, there are no demons, monsters, or devils. Angels stand guard on each of the seven terraces and watch over the penitent. In the Inferno, punishment serves to further immerse the damned in their vice. The torment is so great that they blaspheme God and seek to end their pain. On the other hand, the penitent of the Purgatorio patiently and willfully accept their punishment because it is only through pain that they might be cleansed of vice.
According to Dante, Purgatory is a mountain with seven terraces, and was created when God cast Lucifer out of Heaven as punishment for his rebellion. As Satan crashed to the ground, he displaced a large mound of earth which would later become Mount Purgatory. The pilgrims must climb each of the seven terraces which represent one of the seven deadly sins. As the weight of sins is lifted from them, they rise to next terrace with greater ease and eventually make their ways towards Paradise.
Terrace 1: The Proud
Terrace 2: The Envious
Terrace 3: The Wrathful
Terrace 4: The Slothful
Terrace 5: The Avaricious and Prodigal
Terrace 6: The Gluttonous
Terrace 7: The Lustful
Ante-Purgatory lies between the shores of Mount Purgatory and the First Terrace. In this place, Dante and Virgil meet the souls of the excommunicated and the late penitents. After climbing all seven terraces and reaching the summit, the pilgrims drink from the Lethe and the Eunoe Rivers in Terrestrial Paradise. The waters of the two rivers allow the penitent to forget their past transgressions and to remember only their good deeds.
After passing through Terrestrial Paradise, Dante enters Heaven, the dwelling place of God, the angels, and the blessed. The poet's vision of this eternal place of joy was heavily modeled after the ptolemaic system of astronomy whereby a stationary earth is orbited by the sun, the moon, and the planets. Dante's Heaven is comprised of nine spheres which are moved by the nine orders of angels.
Beatrice explains to Dante that all souls in the Paradiso are eternally blessed, but because of his human limitations, will appear to him in a kind of hierarchy. Beatrice makes clear to Dante that although the blessed may experience the beatific vision differently, they are all equally contented and dwell in the Empyrean.
First Sphere: The Moon: The Inconstant
Second Sphere: Mercury: The Ambitious
Third Sphere: Venus: The Lovers
Fourth Sphere: The Sun: The Wise
Fifth Sphere: Mars: The Warriors of the Faith
Sixth Sphere: Jupiter: The Just Rulers
Seventh Sphere: Saturn: The Contemplatives
Eighth Sphere: The Fixed Stars
Ninth Sphere: The Primum Mobile: The Angels
After making his way through the nine spheres of the Paradiso, Dante ascends to a mystical place beyond the physical realm: The Empyrean is filled with light, joy, and beauty and is devoid of space and time. It is the eternal resting place of the blessed and the home of God. In the Empyrean, Dante sees a vision of a large white rose. All of the blessed, including his beloved Beatrice, are seated inside its petals.
A beautiful angel ferries the penitent across a river. As the souls reach the shores of Mount Purgatory they sing Psalm 114, "In Exitu Israel de Aegypto". 
In exitu Israel de Aegypto, domus Jacob de populo barbaro, facta est Judaea sanctificatio ejus; Israel potestas ejus. (Psalm 114.)
As Dante passes through the Gates of Purgatory he hears a heavenly chorus singing "“Te Deum Laudamus”. 
Te Deum laudamus: te Dominum confitemur. Te aeternum Patremomnis terra veneratur. Tibi omnes Angeli; tibi caeli et universae Potestates; Tibi Cherubim et Seraphim incessabili voce proclamant: Sanctus, Sanctus, Sanctus, Dominus Deus Sabaoth. Pleni sunt caeli et terra maiestatis gloriae tuae. Te gloriosus Apostolorum chorus, Te Prophetarum laudabilis numerus, Te Martyrum candidatus laudat exercitus. Te per orbem terrarum sancta confitetur Ecclesia, Patrem immensae maiestatis: Venerandum tuum verum et unicum Filium; Sanctum quoque Paraclitum Spiritum. Tu Rex gloriae, Christe. Tu Patris sempiternus es Filius. Tu ad liberandum suscepturus hominem, non horruisti Virginis uterum. Tu, devicto mortis aculeo,aperuisti credentibus regna caelorum. Tu ad dexteram Dei sedes, in gloria Patris. Judex crederis esse venturus. Te ergo quaesumus, tuis famulis subveni: quos pretioso sanguine redemisti. Aeterna fac cum sanctis tuis in gloria numerari.
1. Citation: Purg. II. 46. Dante Alighieri, and Mark Musa. Dante Alighieri's Divine Comedy. Bloomington: Indiana University Press, 1996.
2. Citation: Purg. IX.140. Dante Alighieri, and Mark Musa. Dante Alighieri's Divine Comedy. Bloomington: Indiana University Press, 1996.
3. Psalms. The New American Bible.
4. Scott, John A. Understanding Dante. Notre Dame, Ind.: University of Notre Dame Press, 2004.