. >> owe semitea. >>> hello everybody thank you for joining us here in joe semitea. we are marking the 125th anniversary of the national park. a natural wonder that draws millions of visitors every single year. and that has presented monumental challenges for over a century. >> i think about the people that saw this for the very first time. >> it is one of the most beloved places on earth. >> it's one of the most iconic spots on the planet. >> to the soaring granite walls of the lower valley. this is a landscape that defies enspripgs. >> now that we've seen it we are off struck with this. >> but from the moment tourists began to come to yoe semitea and fire was literally shoved over cliffs for a light show better suited for a theme park. >> as the fire burns low. >> reporter: the passing years have brought fires, rock slides, flooding, protests, crowds and traffic. >> people have been telling us for years that they want that changed. >> reporter: after 125 years this is a park at a cross roads. so tonight we'll show you how a new generation of park leaders are findin