One Direction in Boston on Sunday
Back in the U.S. to start their tour, One Direction arrived at Logan International Airport in Boston on Sunday night, to hoards of screaming fans.

Beginning their first headline U.S. tour, Harry Styles, Niall Horan, Liam Payne, Louis Tomlinson, and Zayn Malik jetted into the east coast from London.

Dressed in sunglasses and a hoody, Niall Horan offered a thumbs up to their waiting fans while a barefoot Louis Tomlinson appeared to have lost his socks and shoes.

Despite their obvious jet lag, the boys all lined up outside their tour bus as eager fans snapped photos of the Irish-British hitmakers.

Tweeting to his fans, Mullingar native Horan revealed the band had gone straight into rehearsals for the tour.

"Just did a rehearsal for the 1st show tomorrow!" he wrote on Twitter. "Our first headline tour in the US cannot believe this, so excited."

The band will be celebrating this week with the news that their debut single “What Makes You Beautiful” has gone double platinum after surpassing two million digital sales.

According to Focus Entertainment, One Direction’s debut album Up All Night has sold in excess of 600,000 copies in the USA, with 40,188 sales this week.

The One Direction tour kicked off on Tuesday night at the Mohegan Sun Arena in Connecticut, before the band continued onto Virginia, New Jersey, and New York.