# Best locations for large telescopes at high northern latitudes

Large optical telescopes want to be located at high altitude (get above as much of the atmosphere as possible). I get the impression that there is also a preference for low latitude (see as much of the sky as possible). And perhaps also for a location with good weather, so that there will be as few cloudy nights in the year as possible? So for example, many large optical telescopes are on the summit of Mauna Kea, Hawaii; there is also McDonald Observatory in Texas.

Suppose you wanted to put large optical telescopes as far north as possible, but still meet the other requirements, what would be a good location? Looking for high mountains at northern latitudes is an obvious starting point, but how well would that meet the requirement of clear skies? For example, Mount Washington in New Hampshire is the highest peak in the north-eastern United States, but has notoriously terrible weather; this would be an important downside?

You can (probably) do much better than Mount Washington, both in terms of latitude and air quality. For one, you're right about the weather. According to Wikipedia, it is a convergence point for several storm tracks and next to a breeding ground for low-pressure areas. This not only means a lot of clouds, but very turbulent air, which also lowers the quality of the sky. Also, at just a little shy of $2~km$ in height, you're going to find yourself in the middle of all these clouds, which won't be pleasant. Oh, and you should also consider the difficulties of actually building an observatory in such weather.