What classes did you take and how enjoyable was this process?
Princeton is extremely flexible in their course offerings, as many classes cross-qualify for different areas you are expected to intellectually delve into over the course of your four years at the university. Rather than simply viewing courses as fulfilling a history or literature requirement, courses are also grouped into the sort of skills they each require (i.e. Quantative Reasoning, Ethical and Moral Thinking, etc.). So there are so many options to pursue in order to fulfill the requirements.
Your own department that you will commit to at the end of your sophomore year has its own expectations, and you will tackle some of those in your first two years, and the rest in your last two years. Princetonians also conduct independent research during their junior and senior years, resulting in two “junior papers” and one senior thesis. The length varies based upon department. When I was a history major at Princeton, my JP’s were 40 pages each, and my thesis was around 80. This is either the worst or the best part of the Princeton academic experience, depending on your style. I loved it and had a total blast essentially camping out at the library for almost two years of my life. Take that independent work into consideration when you look at Princeton as a school choice, because it’s serious business, and part of why Princeton is (in my opinion) the best Ivy undergraduate experience of all the options. 
It seriously made my graduate school research seem like a breeze.