# How Far can you see from tall bulidings? Or, how far can they be seen?

I was reading, and apparently, you can see Rochester, New York from the observation deck of the CN Tower in Toronto, Ontario. I think Eve once mentioned that she can see the Empire State Building in New York from her apartment in New Jersey. So, how far can you see from tall buildings, and from how far can they be seen? What are examples?

:bump:

From Architechture Today by The Frantics; done as a radio show with a hyper-enthusiastic host interviewing an architect:

It depends on atmospheric conditions. Did you mean for this to be in GQ?

You can see the Sydney skyline from the Blue Mountains, including one spot on the highway where you see it then lose it again for a long time. That spot, I’d estimate to be approximately 100km from central Sydney as the crow flies. What amazes me is that you can clearly see the slender stem of Sydney Tower from that distance (the thing is only wide enough for a handful of elevators and a fire escape).

On a clear day you can see 30 miles from the top of the Gateway Arch in St. Louis. Unfortunately, there aren’t that many clear days.

From the observatory at the John Hancock Center in Chicago, you can see across Lake Michigan.

Into Michigan?

Cecil once wrote a column on how far you can see out to sea when standing on a beach.

The same formula (derived by defining a right triangle with one adjacent side equal to the earth’s radius and the hypotenuse equal to the earth’s radius plus the observer’s height, and then solving for the third side with the Pythagorean theorem) applies here. It’s:

Distance you can see in miles approx = 1.2(square root of height in feet)

So if you’re atop a 100 foot building, you can see about 1.2(10) = 12 miles.

This assumes a perfectly smooth earth and no obstructions, which can shorten the distance considerably.

You can see Sears Tower from Gary, Indiana in clear air. That’s 25-30 miles.

The Stratosphere tower in Las Vegas is visible from any point I can think of on the freeways around town. The Mormon temple here is probably 25 miles away on a hill, and you can see the casino tower pretty easily from there.

On that note, you can actually see the Mormon temple from just about anywhere in town, too, if you have a line of sight to it. Green Valley is a town maybe 20 miles away from the temple, and you can easily see it from there.

From the kitchen window of my parents’ former house on Mount Gibraltar (near Bowral) on very clear days you could see Sydney Tower and the arch of the Bridge. That’s about 130km.

Hamilton, Ontario is at the end of Lake Ontario, bisected by the Niagara Escarpment (upper and lower city). From the edge of the escarpment, (depending on the pollution index) you can see the skyscrapers of downtown Toronto. That’s about 45 miles, give or take.

It’s worth mentioning that from the observation deck of the CN Tower, you can see the steam rising off Niagara Falls. I’m not sure how to compute the distance using Mapquest, as it’s line-of-sight and not driving distance. But it’s pretty impressive!

No, you can see across the lake, but that’s it. The view ends at the exact point the lake does.
Sigh.

You can see the Sears tower from the Il and WI borders on the east corner from Lake Michigan. That’s about ~45 miles.

The Sears tower is a 1705’ building, includin antennas, so you get 1.2(41.3) = 49.5 miles.

Auckland’s Skytower is advertised as the tallest tower in the Southern Hemisphere, with a view from the top of more than 80 kilometres. That would be around about the furthest distance it can be viewed in turn – and perhaps further, if not for the topography of our region.

The precise scientific formula involves the radius of the Earth, square roots of enormous numbers and other tedious things, but there are a few short cuts that give quite accurate approximations.

For those still into the miles stuff:

If you’re standing at the top of a ship or building on something as flat as the ocean or the plain of Barsoom, then:

1.23 times the square root of your eyeballs’ altitude in feet gives you the maximum distance to the horizon in miles.

And for those not into the miles stuff:

3.57 times the square root of your eyeballs’ altitude in metres gives you the maximum distance to the horizon in kays.

You can see for lightyears from the London Eye if you look upwards on a clear night.

I was in a tall building and I could see the moon and then some.
Come on, just kidding!