After an intensely secretive build-up, Chelsea Clinton (30) and her hedge fund manager beau, Marc Mezvinsky (32), were to marry on Saturday at a star-studded wedding outside New York.
Former Democratic president Bill Clinton and Secretary of State Hillary Clinton were to attend their daughter's big day in Rhinebeck, a rural retreat for New York's elite.
The news blackout has fed a media frenzy, with news teams flooding tiny Rhinebeck to cover what's variously been dubbed the wedding of the decade, century, millennium, or just plain royal. Other details were kept secret right to the eve of the nuptials.
Ceremonies were set to take place at the grandiose Astor Courts house in a wooded area near Rhinebeck.
Security tightened rapidly as Saturday approached and the airspace over Astor Courts was declared a no-fly zone. Road access was also due to be restricted.
Bill Clinton, looking trim after having been instructed by his daughter to lose weight, arrived in Rhinebeck and briefly met crowds on Friday.
"I admire him. Hillary feels the same way," he said.
Unconfirmed media reports said guests include TV chat queen Oprah Winfrey, Hollywood mogul Steven Spielberg and possibly former British premier John Major.
President Barack Obama won't be there — he says he wasn't actually invited and that in any case two presidents would be one too many at a wedding.
Estimates by wedding planners have put the likely cost of the bash at anything between $3 million and $5 million.