FLORIDA KEYS - The maid of honor and best man relaxed on their knees in the sand. The groom swam into view and settled into place. The bride, her veil gently billowing in the current, gracefully floated into place next to her husband-to-be. To the accompaniment of bubbles, the ceremony began.

For a truly unique and memorable experience, couples should consider holding their nuptials in the Florida Keys National Marine Sanctuary's warm, clear water, surrounded by colorful corals, softly waving sponges and rainbows of reef fish.

In the Keys, it's easy. Many dive shops have been arranging underwater weddings for years. They can work with scuba-certified brides and grooms, prepare non-divers in the wedding party for the experience, even help mom and dad enjoy their first undersea excursion.

A word of warning, though: it's nearly impossible to wipe away tears while wearing a dive mask, and handkerchief's are of no use under water.

And unions of the deep are perfectly legal, if conducted in accordance with Keys county ordinances: "A marriage may be performed by regularly ordained clergy, judiciary, State of Florida notaries, the Clerk of the Circuit Court and Deputy Clerks."

In the case of an underwater wedding, the official also must be a certified diver - not difficult to find in the Keys.

The dive shop will help the betrothed couple choose a site that combines safety, comfort and beautiful surroundings. Details like flowers (plastic is highly recommended for the ceremony itself) and the reception (humorously referred to as the "out-gassing" party) also can be arranged.

And in the Keys the underwater theme can even be extended to the honeymoon. Clothes and personal items must be packed in the waterproof suitcases provided to couples spending their first night of wedded bliss at Jules Undersea Lodge www.jul.com, in Key Largo. Currently, it's the only subsea overnight accommodations in the world.

In the Key Largo area, contact Amy Slate's Amoray Dive Center (www.amoray.com), Horizon Divers (www.horizondivers.com), and Atlantis Dive Center (www.weddingsinthekeys.net).

Islamorada area operators include Holiday Isle Dive Shop and Conch Republic Diverswww.conchrepublicdivers.com.

In Marathon, contact Hall's Diving Center hallsdiving.com/halls/index.htm and Tilden's Scuba Center www.tildensscubacenter.com.

A perennial favorite in Key West is Tropical Mike. He can be reached through Captain's Corner Dive Center www.captainscorner.com. Another experienced shop is Dive Key West www.divekeywest.com.