<p>top-tier research university, around 3,500-9,000 undergrads
strong in the sciences and has some notable faculty in physics or astronomy
a "flexible" core curriculum (i.e. you can select your class from within an area)
proximity to a major city
nice campus (i like gothic-style buildings, but they don't have to be)</p>
<p>georgetown (perhaps?), UCLA (it is inside the city though), and in a certain way,the ivies too (although they have more grads than undergrads). And also, how important are sports for you? If they are, then Duke is perfect, I agree</p>
<p>Dartmouth is about as far from a city as any school you'll find. It's not particularly strong in sciences and there isn't a gothic building on the campus.</p>
<p>Don't know about physics or astronomy, but Northwestern seems to fit the bill (in terms of size, core curriculum, proximity to a large city, and nice campus).</p>