Ariana Grande's One Love Manchester Benefit Concert Goes Off Without a Hitch

Ariana Grande and the stars she corralled took the stage for her One Love concert in Manchester ... and they left quite an impact on the city after a horrific terror attack.

Ariana performed throughout the 3 hour benefit concert with the likes of Miley Cyrus, Katy Perry, Justin Bieber, Coldplay, Black Eyed Peas and a number of other acts and guest appearances that filled the Old Trafford Cricket Ground arena with music and good vibes.

Some highlights included Ariana's manager, Scooter Braun, having an emotional moment onstage while introducing Ariana mid-set; Miley Cyrus and Katy Perry paying tribute to the Manchester victims; Mac Miller joining Ariana onstage; Bieber's unifying words; Coldplay blowing away the crowd with an epic performance; Liam Gallagher from Oasis crashing the show; and, of course, Ariana singing an emotional "Over the Rainbow" cover to close things out.

The event comes just a day shy of 2 weeks since the bombing after her show in Manchester killed 22 people ... and 1 day after a second terror attack in London that killed 7 and injured at least 48.

As we reported ... the show sold out in 6 minutes and security measures were tightened up in anticipation. Guests of her original concert in Manchester were allowed to see Ariana again for free.

Seems like everything went off without a hitch. They raised more than $275,000 by the end of the show.