The U2 360° Tour was a worldwide concert tour by rock band U2.Launched in support of the group's 2009 album No Line on the Horizon, the tour visited stadiums from 2009 through 2011. It was named for a stage configuration that allowed the audience to almost completely surround the stage. To accommodate this, a massive four-legged supporting rig, nicknamed "The Claw", was built above the stage, with the sound system and a cylindrical, expanding video screen atop it. The tour was claimed by U2 to be "the first time a band has toured in stadiums with such a unique and original structure."

In an era of declining CD sales, U2 360° was expected to be a major source of income for the band. Every date of the tour sold out, many within minutes of tickets going on sale. To account for the long amount of time required to assemble and transport "The Claw" between dates, three separate stage structures were required on tour. The 360-degree production increased the capacity of venues by up to 25%, leading to attendance records at over 60 venues. The 2010 North American leg of the tour was postponed until the following year after frontman Bono suffered a serious back injury. Various themes were used during the shows; portions of the concerts featured outer space themes, due to the resemblance of "The Claw" to a spaceship. Pre-recorded messages from the International Space Station were incorporated into the shows, as were sociopolitical statements from Desmond Tutu and Aung San Suu Kyi. The setlists were adjusted for each year of the tour; for the 2010 shows, unreleased songs were debuted live, while for 2011 legs, the group performed more 1990s songs to mark the 20th anniversary of the release of Achtung Baby.

Comprising three legs and 110 shows, the tour began on 30 June 2009 in Barcelona, Spain and concluded on 30 July 2011 in Moncton, Canada. It visited Europe and North America for two legs each, while making one-leg visits to South America, Africa, and Oceania. U2 won Billboard Touring Awards for highest-grossing tour in 2009 and 2010, and for the best box score at a single venue in 2009 for shows at Croke Park in Dublin. A 2009 show at the Rose Bowl in Pasadena, California was filmed for the concert video U2 360° at the Rose Bowl and was streamed live over YouTube; the concert set a new US attendance record for a single headlining act. The tour was generally well-received by critics and fans. By its conclusion, U2 360° had set records for the highest-grossing concert tour with $736 million in ticket sales, and for the highest-attended tour with over 7.2 million tickets sold.