Absolutely!  Prospective graduate students tend to have several potential programs in mind, but it is certainly not necessary—or even feasible—to visit them all.  I suggest visiting your top two choices.  This becomes more important if you are looking at doctoral programs, as you’ll be living in the respective place for longer than if you are doing a master’s  The internet can give you a great sense of campus, your prospective department, and the city where the campus is located, but it can only provide you with so much.  You need to determine if you can actively picture yourself living and thriving in a particular place.  If there are things intrinsically important to you and that keep you sane, make sure it will be available in your new location.  A campus visit can show you what the campus and community have to  offer.

Many students are concerned when to visit.  You can visit at various times: before applying, after you have been accepted, or once you’ve made your decision.  Some graduate programs require an interview, so be prepared to use that time constructively to see the town and meet other people in the department.

Here are some tips to get the most out of your campus visit:

1. Start by contacting the secretary or assistant in your prospective academic department.  He or she will help determine a good day to visit when faculty and graduate students are able to meet with you.
2. Spend some time researching the department (hopefully you’ve already done this!).  Take note of faculty research interests, classes you’re interested in, and even other graduate students.  If there are particular people you’d like to meet with, mention this when you contact the department secretary.  He or she will either set up meetings for you or provide you with contact information.
3. Use time with faculty members and other graduate students to get a sense of the department and the environment. This is a good way to see how you fit within the department.
4. If there are particular places on campus you’re interested in seeing, see if you need to request a tour ahead of time.
5. Plan on giving yourself a full day, especially if you have meetings with multiple people in the department.  You don’t want to rush your experience and allowing yourself at least one day will give you time for seeing the town as well as campus.  Personally, I stayed the night, had meetings early the next morning, and used the afternoon to apartment-hunt.