EXCLUSIVE: Paris Hilton's European Vacation -- "We're Having Such A Lovely Time"

Paris Hilton and boyfriend Doug Reinhardt are mixing business with pleasure on their whirlwind trip through Europe.

First stop: Budapest where Paris celebrated the launch of her clothing line at The Coin Store.  Hungary apparently loves Paris because the store's first order sold out immediately and they've already re-ordered.

Friday night Paris and Doug went on to the Venice Film Festival premiere of Bad Lieutenant: Port of Call New Orleans starring Nicolas Cage and Eva Mendez.

The couple was on hand to lend support to Doug's business partner, Alan Polsky, a producer on the movie. The hotel heiress rocked the red carpet in a couture gown by British designer, Jenny Peckham.

"We are having such a lovely time," Paris told RadarOnline.com.  "Venice is such a beautiful city and the shopping is amazing. Loves it!"

On Saturday, Doug took his favorite girl shopping in Venice.  "Doug whipped out his black Amex card and took Paris on a major shopping spree," an eyewitness told RadarOnline.com. "They went to Cartier where he bought her the entire diamond Panther collection of rings, necklaces, and bracelets.

"He topped it off with the diamond-encrusted Cartier LOVE bracelet, which cost a cool $80,000. Doug told the salesman that money was no object, and he wanted to make his girl happy. Paris loves being treated like a princess."

Don't we all!