With this year's Tour of California attracting massive crowds - an estimated 280,000 fans lined the streets of San Francisco for Sunday's prologue - the race organisers are reminding spectators of the need for "race etiquette and conscientious behaviour" whilst visiting the event.
"We are guests in the communities we race through and are only borrowing the road," said Assistant Technical Director, Chuck Hodge. "If our race entourage and the race spectators show courtesy and enthusiasm along the route, it will go a long way towards helping the sport of cycling become even more accepted."
Aside from the obvious need to keep off the course while 144 cyclists come hurtling past, the organisers are asking that fans use "sidewalk chalk" instead of paint to write messages on the road and also keep dogs and small children firmly leashed and under control.
Last year an estimated 1.3 million spectators came out to watch the race and organisers are expecting even larger crowds this time round with 12 cities hosting the race along a 650 mile route.