I’ve seen:
Golden Gate Bridge – the thing about this one that really made me think…it was 75 years old last time I saw it, while a bridge where I live had just collapsed after about 40 years…the technology that went into that bridge is awe inspiring considering how long ago it was built.
Grand Canyon – essentially a big hole, but the scope is rather intimidating up close.
Leaning Tower of Pisa – words can’t describe seeing this up close, you feel like you’re living inside a painting.
The Colosseum – again, makes you wonder how so long ago they figured out how to make something for the ages, while these days you buy something and it breaks the 3rd time you use it.
Big Ben – A giant clock, cool and all, but kinda boring
Mount Rushmore – a really long, curvy drive, followed by a long hike, but still pretty neat to see in real life.
St. Paul’s Cathedral – just thinking about all of the historical figures buried right under the ground you’re walking on kind of boggles the mind.
Westminster Abbey – you’re surrounded by history, it’s astounding.
Niagra Falls – Really two falls, an American and a Canadian falls…breathtaking, and my favorite part, there’s an actual border between the US and Canada that you can straddle.
Four corners – interesting to stand in 4 states at once.
Hoover Dam – much better when the river isn’t dried up.
Trevi Fountain – very cool architecture
Spanish Steps – people who look like they stepped out of a fashion magazine congregate here at all hours
I know I’ve seen many others, but that’s all I have time for right now.