Cyrus celebrated the hallmark birthday at an over-the-top Disneyland celebration on Sunday - even though she doesn't actually turn 16 until Nov. 23.
The theme park was closed for the supersized soiree, which included a four-song performance by the teen queen and a fireworks display above Sleeping Beauty Castle and 16 giant inflatable candles.
"Miley is really hard to surprise," her father Billy Ray Cyrus said at the event.
Organizers estimated over 5,000 people attended the special party, which cost US$250 ($NZ396) a ticket.
On the event's purple carpet - that's Cyrus' favorite colour - the star of the Disney Channel's Hannah Montana bragged that her parents bought her a new puppy for her birthday. What else does Cyrus want for her birthday? A new car? Perhaps a later curfew?
"My parents shut down Disneyland for me, so I'm good for a while," Cyrus said.
Cyrus' father opened up for his daughter with a few of his own songs, including Achy Breaky Heart.
His daughter donned a white ruffled skirt and jersey-like vest with "Sweet 16" printed on the back for her truncated concert. At one point, Cyrus boarded a boat in the park's Rivers of America and crooned such tunes as Breakout and G.N.O.
Throughout the evening, several popular attractions, such as Big Thunder Mountain and Pirates of the Caribbean, remained open to partygoers. Additional activities, like receiving a Hannah Montana makeover and playing the upcoming Disney Interactive Studios rhythm video game "Ultimate Band," were also made available to attendees.
Partygoers ogled celebrities roaming around the park throughout the party. David Archuleta and his entourage skipped the line to ride Space Mountain. Jennie Garth and her family ducked out before the fireworks display capping the celebration.
Other stars in attendance included Steve Carell, Cindy Crawford, Tyra Banks, Jennifer Love Hewitt, Heather Locklear and Demi Lovato.
Disney used the event to promote their upcoming "What Will You Celebrate?" marketing initiative, which encourages tourists to take "celebration vacations" with their families. Beginning in 2009, guests at Disneyland and Walt Disney World in Florida can gain free theme park admission on their birthday with a valid ID and proof of birth date.
Over at Disney's California Adventure, Disneyland's sister theme park, an entirely different celebration was occurring during the Sweet 16 event: the 11th annual Gay Days Anaheim, an unofficial gathering of gays and lesbians at the Disneyland Resort. Event producer Jeffrey Epstein said Cyrus' affair didn't conflict with Gay Days Anaheim.
"We're happy to share our big weekend with Miley," said Epstein. "While it may be a small world after all, we think it's big enough for both groups to have a blast."
