Check out this great old map of Roland Park in 1941.

Source: University of Maryland
This is what it looks like today, courtesy of Google.
[googlemaps https://maps.google.com/maps/embed?pb=!1m14!1m12!1m3!1d3084.9451597669!2d-76.62279438153462!3d39.35747848195301!2m3!1f0!2f0!3f0!3m2!1i1024!2i768!4f13.1!5e0!3m2!1sen!2sus!4v1393200166891]Thanks to the awesome collection available at the University of Maryland.