On the Road Part 3, Chapter 11
They take a bus to Detroit and Dean sleeps all the way while Sal tries to have a conversation with a country girl. Dean and Sal stay in an all-night movie house for the night and encounter lost people of all kinds. Attendants sweep up in the morning. Sal thinks if he were swept up with the trash, Dean would never find him. They find a ride to New York for four dollars a piece and Dean is in another frenzied state.
As they cross into Toledo, Sal realizes that he has been crisscrossing the nation like a traveling salesman. Dean drives through Pennsylvania and into New York. They stay at Sal's aunt's new apartment on Long Island for a while. Five days later, they go to a party and Dean meets a girl named Inez with whom he falls in love immediately. He pledges to divorce Camille.
"Not only that, but a few months later Camille gave birth to Dean's second baby, the result of a few nights' rapport early in the year. And another matter of months and Inez had a baby. With one illegitimate child in the West somewhere, Dean then had four little ones and not a cent, and was all troubles and ecstasy and speed as ever. So we didn't go to Italy." Part 3, Chapter 11, pg. 247.
Instead of Italy, Sal stays in New York for a while.