Petřín Lookout Tower
I've been told it's the best view in Prague, and I believe it! Not as daunting as the Eiffel Tower to climb, it is worth ascending or descending by the stairs. It's the only way to get to the first viewing level, which is unobstructed. Once you make it to the top there will probably be someone standing there looking down the stairs at you sweating your tail off but it's worth it!