Finding transportation in Baltimore is not challenging; rather, getting around without getting killed is the real art.
Alright, that was a joke. I don't want to be blamed for the large number of transfers next year. But really, there are numerous easy ways for you to travel around the city.
There are several shuttle buses on campus that take you to different parts of Baltimore. Throughout the week, the Collegetown shuttle runs regularly between Towson Center (a shopping mall you'll learn to love) and Hopkins. It also stops at Loyola College, College of Notre Dame, Goucher College and MICA. It's particularly convenient for those who cross-register at the other universities.
On Fridays and Saturdays, the shuttle runs to Inner Harbor as well. There is also another route that goes to Arundel Mills but that does not stop by Hopkins. Grab a shuttle schedule from the Security Office behind Shriver Hall and hop onto the bus in front of the MSE Library.
Another popular shuttle runs from the Homewood Campus to the Medical Campus in Eastern Baltimore. You can get off at Penn Station and Peabody Institute in Mount Vernon along the way. Many students who do research at the former or take music lessons at the latter rely on the shuttle heavily. It's also another easy way to reach Inner Harbor (in daytime), as it is only a 15-20 minute walk from Mount Vernon along Charles Street. The shuttles wait in front of the Security Office.
Though not quite a shuttle service, the security escort vans are frequently used by students, especially after dark. In the evening, the vans run a regular route from the Homewood campus to The Rotunda and Superfresh.
After certain hours, the security escort vans are on-call for students who wish to go anywhere within a one-mile radius of the campus. The service ensures your safety while traveling in the night, and drivers are happy to take you grocery shopping, to visit the Korean restaurants, or to go to a party at a frat house.
The MTA buses are also convenient and run around the city at a one-way fare of $2.60. Typically, bus number 11 has a route between Towson area (not Towson Center) and the Inner Harbor, stopping by popular locations such as Charles Theater and Penn Station. You can catch the bus on St. Paul Street just behind the Homewood Building when your schedule falls between the shuttle hours.
Two other types of public transport that you will find useful are the Light Rail and the Metro. Although they do not stop by the Homewood campus, their stations can be found in numerous locations in the city. These trains are very good ways to explore Baltimore since they take you to points of interests such as Lexington Market and Camden Yards.
If you're looking to do something off the public and school run transportation routes, a cab is always the best choice if you don't have a car. Whether you would like to go to Little Italy for a nice meal or the Inner Harbor after shuttle hours, it can be a good deal if you travel with a few friends, each chipping in just a few bucks.