I have been there but only spent a day there. It sucked ( wel it was still awesome but not as good as it could be ) when I was there because it was just before winter so the falls weren't running ( no water runoff from winter yet ) Supposedly the spring is really good for wildflowers, wildlife, and waterfalls. You can get all of the cliche spots from the tourist areas like the tunnel parking lot pretty easily. If you plan on venturing out into the wilderness, I would advise some sort of protection, and perhaps a plan incase you get lost ( GPS, Flare, Strobe light, whistle, matches etc ). And learn about Animals and how to deter them or avoid situations with them. Like Bears and Wildcats mainly. Yosemite park is HUGE though. The valley is the most famous and photographed part, but it takes you like an hour to drive from each end of the park, so its quite a massive area. You could probably spend a year there and not see every part of it. There is also the massive Mariposa Grove with the largest trees which is close to the Southern most entrance. I have been to the mountains in Tennessee, North Carolina, New York, Pennsylvania, Viginia, Vermont, Colorado, and Arizona ( including the grand canyon ) and Yosemite is probably the most beautiful place I have ever been, even in the dullness of late autumn, early winter. You will love it. The only place that I think would come close to matching it, might be the Canadian Rockies ( since much of that area is preserved ) but I have not been there yet unfortunately.