I have read so many travel pieces over the years that have suggested that one monument or another is not “worth it” due to the access, the cost, the crowds and so on. Here is why monuments or major “tourist attractions” are worth it. They are worth it because they make you feel like you have arrived. The image from television, or puzzles or screen savers or childhood stories that you have dreamed about your entire life, is right in front of you and there is nothing better than that moment!
The sea of people flooding Pompeii and the switch back lines into the Coliseum, the torrential downpour and graffiti ridden alleys leading to the Tower of Pisa, or the 15 toll booths on the way to the Monaco are nothing compared to the moment you turn the corner and there it is.
There is no way to describe the moment, no cost benefit analysis that means anything. If it is a dream of yours to see the Eiffel Tower and the lines is 6 hours long, get a baguette and enjoy the journey. The only thing that matters is that you GO if you dream of going. In my experience, it is always worth it because it is so much bigger than the act. It is a lifetime fulfilled. It is an incalculable monumental moment!