h2g2 The Hitchhiker's Guide to the Galaxy: Earth Edition

I think the coolest thing I have ever seen is the view from the top of beautiful Timberwolf mountain in Washington, or the view of the Philly skyline from independence square in Philadelphia

Liquid Nitrogen

I find little things very cool, after I mowed the lawn I saw a going round lobbing bits of grass out its web, I never seen a spider house keep in that way, finding a gelatinous mushroom that looks spookily like an eyeball and giving it poke

The curvature of the Earth from the top of the World Trade Center.

Watching the sun rise on a misty morning from the top of Glastonbury Tor

Star gazing while floating in the ocean

Watching a calf being born.

I know it is soppy and unoriginal but *the* coolest thing I have ever seen was my daughters face for the first time, but that is trumped by the coolest thing in my life ever was hearing her, this plaintive tiny mew, the joy and relief at that sound is indescribable and I well up every time I think of it.

In case it isn't obvious we were prepared for silence, hoping for a mew

The world is full of cool stuff. I couldn't pick out one, so here's a list of twelve:

1. The Antikythera Mechanism, Athens - a geared mechanism built in the 1st Century BC to predict the motion of the sun, moon and planets

2. Eclipse of Sun September 1999 - not total from where I saw it, but 97%

3. Lunar Lander and re-entry vehicles - the actual ones that went to the moon, on display in the Science Museum, London

4. Grand Gallery of Great Pyramid - it's not clear what this strange sloping room was built for, but it's nearly 5,000 years old and still looking good.

5. Hypostyle Hall, Temple of Karnak - the biggest pillars ever made in antiquity, packed together so close you can hardly see through them

6. Golden Head of Tut-ankh-amen - we've all seen this in pictures. I saw it in a dusty glass case in the museum in Cairo.

7. Strokkur geyser, Iceland - when I was there, Geysir (the great geyser) wasn't working, but the smaller one next to it gave an impressive display every few minutes. Camped within earshot of it.

8. Dettifoss, Iceland - biggest waterfall in Europe. It's only one tenth the size of Niagara Falls, but still impressive.

9. The Scream, by Edvard Munch, in a museum in Oslo.

10. Hagia Sophia, the pinnacle of Roman architecture, the biggest church in the world for nearly a thousand years and still impressive 1,500 years after its construction

11. Moone High Cross - a giant teaching aid for early Irish Christians, carved in the 9th Century in a cartoon style with pictures from the Bible

12. Naked Mole Rat Colony, Pacific Science Museum, Seattle. Because these creatures are blind, they're kept in a burrow made from transparent plastic tubes, so you can watch them running around, gnawing at blocks of stone and generally being friendly.

I've seen the sun set in the East.

Were you travelling west in a supersonic plane?

I was travelling north-west on a sub-supersonic plane.

I also saw the sun rise twice on the same day.

The Aurora Borealis over Cork in 2003. Utterly amazing.

A meteor storm in Boston in 2001. Hundreds of meteors a minute.

A sea horse while diving off the coast of Thailand. I was told later it was very rare to see them.

Charles Bridge, Prague, at sunset.

Hmmmm... several things, which I guess my brain must think were cool, as the memorys are still hanging about and do occasionally spring into mind, un-consciously....

Camping out, without a tent, in the lake district and seeing all the metiors all night through...
Seeing the sun rise, off a cliff, slightly to one side of the most easterly point, again after having camped out there all night
Hiking I think in the peak district; watching a car, go up the 'hill' or 'mountain', whatever it was; car circling round it, on the road that went up but around..... and then watching as the car rolled over... and down... and down... and down.... and seeing the young 'men' inside get out and in fits of hysterical laugher as they did so
exploring through some woods/marshes, that I'd been in thousands and thousands of times, and getting through a particularly impassible section, and discovering a hidden little 'clearing', with a natural spring-fed 'pond' in it...
flying 'out of my body', on several occasions, the most rememberable being the I assume 'drug-induced' one, whilst I was in hospital in/just out of a coma... and then having very simular experiences, several times, induced by err, brain-chemicals without any need for external drug--induction
Oh, and whilst at middle school (age 11 or 12?) seeing a mini-tornado thing, create a crop circle, in a field next to the school (well, that's what it damn well looked like was happening ) I'm sure there are otters... but soem things are maybe best left unspoken, or at least unwritten

Liquid Helium

More seriously - I'd second Hagia Sofia - just so stunning and wreathed in a staggering history. In addition in more or less the same place - we get bowled over by The Tower of London - try the Theodosian Walls of Constantinople - 600 years older and about 1000 times the size and still largely intact.

not sure if it's really cool, given what it is, but I once saw two A10 aircraft (aka: tankbusters) carrying out live firing target practice.

The noise they make when firing their bursts of anti-tank weaponry (whatever that is) sounds a bit like - well, we were all soldiers watching it - farting. Very low pitched in bursts of about half a second, three close together.

They fly in fast but when they fire they seem to hover. It's quite an extraordinary thing.

Liquid water at London Paddington.

Had a great lunch at Italian restaurant in Cambridge, which included anchovies, went to catch a train to London, which turned out to be a bus due to engineering works, hot day, took forever, soooo thirsty

Yes I recall going to Portsmouth to visit my sister on what just happened to be the day before the 50th anniverisary commemorations of D-Day.

In the harbour, way off shore but still much mightier than anything else around was the USS Enterprise but in a scary moment two military jets did a very low and loud flyover above us and that's about as scary as I want anything to get. I dread to think how scary it must be if they are firing in anger

Liquid water? Never! Pictures or it didn't happen

@ swl, well to be fair I think a mushroom cloud is cool but you wouldn't want one to be there to be seen by anyone