OSWIECIM, Poland (Reuters) – Riders on the Tour of Poland bike race paid their respects to the Holocaust victims of Auschwitz-Birkenau with a short ceremony outside the gates of the concentration camp Friday. Before the start of stage six of the race, the 175 riders slowly pedaled around 12 km from the nearby town of Oswiecim to Auschwitz-Birkenau and then, in near-silence, removed their helmets in front of some 50 spectators for the ceremony.One rider from each of the 34 countries present on the race, as well as Tour of Poland leader Dan Martin of Ireland laid a single white rose each at the gate.