Why is it said that "Virgil led Dante on a tour of Hell and Purgatory"?

In the case of the Divine Comedy, he used himself as a character to tell the story of the journey from Hell to Purgatory and then to Heaven. Those who displeased him, whether hypocritical politicians or moralistic popes, were sent to hell. And Virgil, the great poet of ancient Rome, as a symbol of wisdom, led him on a tour of hell and purgatory; Miss Béatrice, as a symbol of purity and love, guided him to heaven.

An often-overlooked point here, too, is that the character of Miss Béatrice, in fact, implicates another feature of Dante's literary style - chivalric love.

Dante was so influenced by "chivalric love" that he wrote many lyrical poems in praise of his unfulfilled love for Beatrice di Forco Bottinelli. This woman was the model for Miss Béatrice in the Divine Comedy.

Here's what "chivalrous love" means.

Tracing the origins of chivalric love, partly from the Roman writer Ovid, partly from the Arabic literature of the Iberian Peninsula. It was later summarized by some troubadours, who got the concept: a kind of gratuitous love of a man for a woman in a distant land.

Expanding on this, it means that men are humble knights in the service of women, and the loved women are powerful masters. The knights are loyal and brave, the mistress proud and out of reach.

In chivalric love, the inferior knight usually loves, suffers, and is burdened with the heroic endeavor of attracting the superior woman; and the woman meets this love with passivity. Thus, another great tradition of chivalric love has developed: a gratuitous love with a sense of secrecy and distance.

This tradition, of course, was to have a very strong influence on the society that followed.