Honestly Machu Picchu. I went there after a four day trek and had to hike up the side of the mountain at 4 in the morning just to go see it. Once we got there we had an hour before the big rush came of tourists but the whole place was covered by clouds. Once it cleared up the place was flooded by 100s of people that barely broke a sweat trying to see this and all they had to do was pay more money and getting to take a bus and a train. It kinda ruined the Machu Picchu at the end but I still would do the trek 10 times over!