Pippa Middleton's Wedding at St. Mark's Church with Royal Family and Roger Federer (PHOTO GALLERY)

Pippa Middleton's wedding wasn't technically royal, but there were still princes there ... along with tennis royalty.

Several members of the Royal Family -- including Prince William and Prince Harry -- arrived at St. Mark's Church Saturday to see Pippa -- sister of Catherine, Duchess of Cambridge -- walk down the aisle and marry hedge fund manager James Matthews.

The church is a 12th-century church just a couple of miles away from her parent's home in Englefield, Berkshire. The ceremony is believed to have cost over £250,000.