Manmade: Lightning Field.
Natural: the moon
Natural: Iceland–any part, really. The geysers and glaciers and rock formations.
man made: pyramids, probably. Or Atlantis, if they ever find it.
Man-made: The Hagia Sophia. (I drove across Hoover Dam but couldn’t stop; want to get a better look at it someday. Already seen the Eiffel Tower, Statue of Liberty, Grand Coulee Dam, Hradčany Castle)
Natural: The Alps. (Saw Grand Canyon just a few months ago.)
Kilamanjaro, the top of it.
The pyramids, Athens, Rome, London, the leaning tower of Pisa, Venice.
Too noisy. Grand Canyon and…hmmmm…isn’t there a fabulous bridge in Japan that’s like 20 miles long or something? I’d like to see that.
Stonehenge and…can I say the aurora borealis?
Man-Made: Taj Mahal. I remember reading a thread a while ago (which I can’t be bothered finding) about overrated and underrated tourist attractions. There were varying opinions about most tourist attractions mentioned, but it seemed like everyone who mentioned the Taj Mahal said it was far more spectacular than they ever imagined.
Can’t think of any natural wonders. I happen to live in a country that has all sorts of geological anomalies, so a lot of natural wonders just seem to be larger versions of what I’ve already seen. I guess I’d go for something outside of NZ’s climate, like tropical rainforests or deserts or Antarctica.
Hey you stole both of what I was going to post.
No Fair 
I used to live in Banff and still work there everyonce and a while. Every time I go it still takes my breath away. This was the view outside of where I used to live. It hurts a bit to leave there even when I live only 1.5 hours away.
I also used to live in New Brunswick (yup I get around) and took the bridge to visit a friend in PEI, I was so excited to see it but it wasnt as great as I thought it would be. The sides of the bridge are too high to see over, unless you are in a bus, and it tends to be foggy. I suggest that when you go (if you go) wait for a clear day and pull over before driving across. This is the view when I was past the high point in the bridge and driving toward PEI.
I also recommend if you are in that neck of the woods make a trip to Cavendish in PEI and Hopewell Rocks in NB (just be careful about the tidal change).
Natural: I’d like to spend a week at a science station in Antarcia. To see for myself what that part of the world is really like.
Man Made: The pyramids, I guess. Though a guided tour through the engine room of an aircraft carrier would also be nice.
(I know, I’m weird) 
Great Wall of China. Or ancient pyramids, any continent. Or Stonehenge (and not from behind the fence, I want to walk around the stones them selves).
Natural wonder? I’d like to see the Grand Canyon again. Niagara Falls would be cool, too. Is “Alaska” not specific enough? Because I’d really like to see Alaska.
Angkor Wat.
Antarctica (from a warm cruise liner, of course.)
But only once. For 20 minutes.
Natural would have to be Patagonia
I’ve been to Chichen itza, but Machu Picchu has always been a wish.
I’m too old for either, though.
Man-made is a tie: Macchu Pichu or the Sistine Chapel
Natural phenom: Mt. Everest
Natural: full solar eclipse. Hopefully it won’t be raining on the date & location I select, as it was 40 years ago, the nearest I’ve ever come to such an occasion.
Manmade: Sistine Chapel sounds like a good choice.
Man-Made: The new-ish Millau Bridge.
Natural: Iguassu Falls.
Macchu Piccu
I’m pretty jaded, having seen most of what has been listed, but I’d like to photograph the slot canyons of the U.S. Southwest and I’d like to stay in this hotel for a night.
Natural: The Grand Canyon (cause I just woke up and I can’t think of anything better)
Man-made: Burj Al Arab
And for those of you who would like to see the Taj Mahal, West Virginia has something you might be interested in seeing.
The Palace of Gold is awe-inspiring and surprisingly not well known in this area. If you go, make sure the first time is in the spring or summer when the rose garden is in full bloom…it will be well worth the trip.
You too huh? Only six and a bit years for me, but I’d been waiting for it since the late 1960s and there won’t be another one in this country in my lifetime.
The cloud thinned out enough that I caught a filtered glimpse, but it was way less than I’d been dreaming of all those years.