Inside Princess Olympia of Greece's lavish 21st birthday celebration

Princess Olympia and her father Crown Prince Pavlos celebrated their milestone birthdays with a joint celebration over the weekend. The father-daughter duo were treated to a royal-studded party held at a manor in Gloucestershire on Saturday. The masquerade soirée, whose theme was "Prince and the Revolution," was attended by a number of European royals including Queen Maxima of the Netherlands and Norway's Crown Prince Haakon and Crown Princess Mette-Marit and Rosario Nadal — the wife of Prince Kyril of Preslav.
Olympia, who turns 21 on July 25, stunned for the occasion wearing an embellished gown by Steven Khalil that featured a blush tulle skirt. The birthday girl completed her glamorous look with colorful platform sneakers. The royal's mother and Pavlo's wife, Crown Princess Marie-Chantal also wowed at the lavish bash sporting a show-stopping headpiece by Philip Treacy that paired nicely with her vibrant hot pink gown.
Click through for all the exquisite party pics!

Queen Maxima (L) posed with designer Valentino and Crown Princess Marie-Chantal.
Photo: Instagram/@giancarlogiammetti

The bash also celebrated Crown Prince Pavlos' (pictured with Rosario Nadal) recent 50th birthday.
Photo: Instagram/@giancarlogiammetti

Norway's Crown Prince (left) and Crown Princess (centre), along with designer Tory Burch (second from right) attended the joint birthday celebration.
Photo: Instagram/@giancarlogiammetti

The birthday girl completed her glamorous look with colourful platform sneakers.
Photo: Instagram/@georgefair

Olympia's younger brothers, Alexios (right) and Achileas (left), planted a kiss on guest Paris Hilton.
Photo: Instagram/@alexiosgreece

"It's a revolution! #HappyBirthdayPavlos+Olympia," Nicky Hilton captioned a photo from the party with her sister Paris.
Photo: Instagram/@nickyhilton

Guests including Queen Maxima were dressed to the nines for the joint birthday celebration in honour of Prince Pavlos and his daughter Olympia.
Photo: Instagram/@realmrvalentino