The Royal couple hasn't arrived yet and already their visit to Calgary is stirring up controversy.

Letters from animal rights groups have been sent to Clarence House, the official home of Prince William and the Duchess of Cambridge, asking the coupe to boycott the Calgary Stampede events including the Stampede parade.

The letters say the Stampede promotes animal cruelty and cautions the royals that any involvement will be seen as an endorsement of animal abuse.

The League Against Cruel Sports in the UK says it would be like the couple attending a cockfight when visiting India, and points out rodeo has been banned in Britain since 1934.

"It would be very odd for an heir to the British throne to be attending an event that was outlawed by an act of parliament to which his grandfather gave royal assent almost 80 years ago," says Steve Taylor of the LACS.

Closer to home, the Vancouver humane society is sending the same message. The society, in a letter to the Duke and Duchess of Cambridge, states the Stampede is an event "in which more than 80 animals have died since 1986. The rodeo is a brutal spectacle of cruelty that subjects the animals to unnecessary pain, stress and fear."

The Stampede Board says it agrees with the Vancouver humane society on one point.

"We are opposed to anything that is cruel or causes animals any stress," says Doug Fraser of the Stampede board.

The Stampede board can't say what the role of the royals will be during their visit, but they have been invited to help open the "greatest outdoor show on earth".

Whether they stay away or embrace the "when in Rome" philosophy, it's likely to cause controversy either way.

In recent years, the Calgary Stampede has introduced safety rules that include mandatory rest days for horses, fewer outriders in the chuckwagon events and more animal checks done by veterinarians.