Britney Spears recently gifted Mexico fans with a free show in Mexico City, which attracted more than 80,000 people, the singer has revealed.

On Tuesday, Spears tweeted a panoramic pic of the crowd at Monumento a la Revolución with the message: "Thx to the 80,000 fans that showed up in Mexico City. Can't imagine what you'd do if u had to go to the bathroom! Xxoo."

We can't either. The image shows a sea of people going back as far as the eye can see. The fans are, as the Beastie Boys would say, "packed like sardines in a tin," but would obviously endure any kind of claustrophobic situation for the chance to see the pop star live, and for free.

The concert took place on Sunday, Dec. 4, and was broadcast around the entire country. Spears was also in Mexico to perform three paid shows in addition to the free concert, which was described by government official Marcelo Ebrard as an event to "kick off the Christmas holidays."

That's some Christmas present! Brit will head to the Dominican Republic on Thursday to perform at Santo Domingo's Estadio Olimpico, before heading to San Juan, Puerto Rico for her last show of 2011 at the Coliseo De Puerto Rico.