Mist from the Lower Cascade, Upper Chilnualna Falls
Somewhere down there is a fabulous waterfall. Too bad you have to hike half a mile or so away to see it. Would it have killed anyone to build a viewing platform for the biggest cascade in Chilnualna Falls?
Actually, it likely would have. When you catch your first view of this section of the falls, scan the sheer granite face through your binoculars and figure out how you would have built an overlook onto or out of that. Any practical ideas you conceive would probably involve dynamite, space elevators, or cave beavers. (Please note that building a staircase out of the skulls of the people who died trying to build a staircase of human skulls would not fully fit the definition of practical. So stop thinking about that one already.) If you want a truly safe project, a good standard would be to rule out anything you couldn't get through airport security, which eliminates the essential supplies for all these technologies, along with other known killers like nail files and small bottles of water.