Columbia was designed with sustainability in mind!
James Rouse designed the "new city" of Columbia as five villages, each with meeting places, schools, shops, pools, and other amenities located within walking distance along pathways through woodlands and open space areas. The villages were to be linked to Town Center by a transit route which ran along a designated right-of-way originally planned for a monorail. Unfortunately political pressure from a politician in a nearby state resulted in the monorail being built in West Virginia. However, the 50 ft wide right-of-way, is still largely intact and owned by the Columbia Association.
"Town Center" was designed to "capture all the vitality and excitement of urban life in a setting of natural beauty". Until fairly recently that area (now known as "Downtown") included all of these major features including Columbia Association headquarters, entertainment venues (Merriweather Post Pavillion, Toby's Dinner Theater), one of the nation's first shopping malls and sizable areas of green space including Lake Kittamaqundi and Symphony Woods.
This is a model of an early design for "Town Center." Notice all the trees -- and also the transit bridge that crosses the lake and extends over US29.
Four decades later Columbia had grown to include several more villages, each following Rouse's model used for the original ones - apart from being linked by a transitway.
This portion of a Columbia Street Map published by the Columbia Association in 2013 map shows how Town Center had grown although it was still surrounded by open space and Symphony Woods was still intact.