US pop superstar Taylor Swift will take to the stage on Friday night, the first in a series of shows expected to draw the biggest audiences of her career.
Crowds at the MCG are tipped to reach 260,000 across three nights.
The Melbourne shows will be followed by four sold-out concerts by the 14-time Grammy winner at Accor Stadium in Sydney from next Friday.
The lines were long at merchandise stores from early on Friday before fans started to queue at gates for the ticketed event from 2.30pm.
Stadium operators previously pleaded with fans who don't have tickets to stay away from parkland around the venue, over concerns people would gather and cause safety issues.
The Eras tour takes in every phase of Taylor Swift's career in concerts that run more than three hours, from her Speak Now album to Reputation and the more recent Midnights.
Fans spent hours queuing and waiting on websites to secure coveted tickets to the show, with a second last-minute release on Thursday and the promise of further tickets being released on show days.
The concerts are expected to provide an economic boost for Victoria and NSW, with Swifties from interstate and overseas booking flights and hotels.
Melbourne's free tram zone has been extended to the MCG while extra train, tram and bus services will be running on Friday, Saturday and Sunday.
Jacinta Ross, Miranda Ross and Peggy Magee travelled to Melbourne from Brisbane for the event. (Con Chronis/AAP PHOTOS)
Concertgoers from regional Victoria were urged to make alternative arrangements as some V/Line rail staff staged another round of strikes on Friday, but services returned to normal by late morning.
The area around the MCG is expected to be busy on concert nights with surrounding roads closed off in addition to A-League Men matches at nearby AAMI Park on two nights and NBL at John Cain Arena on Saturday.
Victorian Premier Jacinta Allan will be among thousands of fans attending the tour, as the state recovers from devastating storms and bushfires.
On Friday, Ms Allan said it didn't feel right to be talking about the concert while on the ground in Mirboo North, Gippsland.
"I reckon there's a fair few people in Gippsland who would've liked to have attended as well who are currently out on chainsaws," she told reporters.
"I'm sure it will be a great showcase for our city."
