edit: yay everything's been answered already
Ok. The bird is a 2cy Red-Tailed Hawk (
Buteo jamaicensis), meaning it was born on last year (told by uniform coverts and secondaries, no moult marks, pale and unformly worn remiges.
It's common in most of the continental North America, and has also been recorded in Europe. Common refers to visibility; large raptors are seldom, if ever, as numerous as smaller birds.
I meant more in terms of numbers rather than species. For instance peregrine falcons would do rather well in London. There are plenty of pigeons to eat and the city isn't actually that full of skyscrapers.
And the suburbs are even better for them.
The main reason for this is called pesticides. Numbers of Peregrine Falcon collapsed dramatically in 1950s-1970s, and even in sparsely-populated Northern Scandinavia numbers are only as of now slowly climbing to somewhere near the previous levels. This is actually a pretty complex thing, but the current consensus is that as long as the species is uncommon, it favours the best breeding conditions it can. Combined with raptor persecution this has dramatically shifted the fitness from bold to the shy.
So, because Peregrine is uncommon and only sloooowly recovering in Europe, it's more likely that the new pairs will nest on the more optimal areas. Also, the Peregrine Falcon genome in eastern USA is a bit of mess, introduced birds from wrong subspecies and all kinds of jazz :/
Raptors as such actually like cities. Easy food, especially in winter. Where I live, we have several courting Eagle Owls, lots of Goshawks, some Sparrowhawks, and accidentally Merlins and sometimes even large falcons. Kites favour towns and villages, and in Indian dumps you can have flocks of tens of thousands of Black Kites. Lowland towns actually have more in common with mountains than their surrounding areas. This shows in avifauna - swifts, pigeons, black redstarts..
edit: Wiki says there are Peregrines in London, dunno about that.