What's life like at Columbia?

<p>I'd really like to know what life is like at Columbia. Do you find yourself around the city often, or do you mainly stay on campus? Is the student body close-knit or more spread out? Are the academics really uptight or challenging but still allowing some free time? What type of students does Columbia look for? What are the professors like, is it a school where it's impossible to get a 4.0? Thank you :) </p>