. >> this particular pea taun is the most famous pe tan in the world. in the first ever assent of the nose route. >> i'm on a facility where people can come learn about the history of climbing. >> as for stacy brown rock climbing with her new husband in yosemite she wants to see yosemite on permanent display forever. >> yosemite's a good reminder that we do need to preserve what we have. >> reporter: preserving what we have is no small task. so up next the man is in charge of the big picture. when it comes to managing yosemite for generations to come and how you can become part of the park by becoming a volunteer. even,,,,,,,,,,,,,, ,, >>> with so much traffic here you're bound to end up with some litter and by some we literally mean tons of it. >> i don't understand littering even in the city but especially in a beautiful place like this. i don't get it, but people do it. >> reporter: whether they intend to or not the millions of people visiting yosemite leave a lot of litter. and every september for one week hundreds of volunteers pick it all up. the