child, ishmael, the angel came and at his feet sprung a well which is called, from hagar's words, zamzam. and it is a kind of holy water. then they will run between the hills of safa and marwah in the way that hagar did. mina is a tent city. and they will live in this tent and perform five daily prayers. the prophet mohammed, when he made his pilgrimage, he came to the top of this hill. he gave his final sermon. it is the belief that after one completes this day on arafah, that all of your sins are forgiven. the prophet instructed his companions to collect some pebbles. and the next morning, after arafah, come and throw, symbolically, their pebble, like abraham threw at the devil when he was tempted. while we are in mina, throwing our stones, people in mecca are celebrating eid. it's like thanksgiving on steroids. we sacrifice a sheep, and we give that food to the needy around our planet. my hajj is not valid unless i make the sacrifice. >>> that's our program for now. i'm bob abernethy. you can follow us on twitter and facebook and watch us anytime on the pbs app for iphones and ipads.