Prince Harry was in the USA this week -- spreading cheer and making girls blush throughout the land.

The sexy red-headed (and single!) royal was in Washington, D.C., to accept a humanitarian leadership award (which Bono previously received) from the Atlantic Council at the Ritz-Carlton (at 22nd and L Streets NW). The 27-year-old hottie received the award for the work he does with his bro, Prince William, to help wounded warriors and military veterans.

But, enough about that.

Harry's fans -- which included men, women and a whole bunch of screaming gals -- arrived hours before the AC event so that they could wait on the sidewalk and try to spot the young royal.

Some of the girls even admitted to doing crash diets, buying new outfits and sporting padded bras ... just in case the Prince caught a glimpse of them.

Welcome to America, Harry. 

 P.S. Ladies, sorry we couldn't tell you earlier, but the Prince rested his lovely red head in Arlington, Va., on the nice pillows at the Ritz-Carlton in Pentagon City.

VIDEO: Prince Harry Arrives At The Ritz Carlton For Atlantic Council Event

PHOTOS: Prince Harry In Washington, D.C.
 

 A crowd waits outside the Ritz for Prince Harry.

The camera phones go wild as Harry arrives.

Prince Harry walks to red carpet.

The royal handshake.

Prince Harry does a little royal schmoozing.

Prince Harry arrives at the Ritz for Atlantic Council event.

Prince Harry enters the building.

We've got your back, Harry.

This is the ballroom (pre-event) where Prince Harry was honored by the Atlantic Council.

Prince Harry talks with Jill Biden at a reception with wounded U.K. service members at the British Embassy early Monday.

Prince Harry greets "Warrior Games" participants at the British Embassy early Monday.

Prince Harry leaves Washington, D.C., via Dulles airport Monday evening.
 

Sources: The British Embassy, the Atlantic Council, Michelle Basch and Team Glittarazzi (Ali, Mark, Jed and Greg). And, special thanks for @HWalesWatch - love you!