Many cities grew haphazardly, with new streets added along with construction or built as required to connect neighborhoods. Some modern cities and a few ancient planned cities like Mohenjo-daro and Islamabad were laid out as grids.
Grid layouts were typically planned before settlement with streets laid out neat, orderly grids to facilitate rapid traffic flow, both of people and vehicles. Grid layouts support a large number of abutting lots, with streets laid out in advance so that all lots are within a short distance of both north-south and east-west boulevards. Grid layouts aid in the navigation of what would otherwise be a tangled and confusing jumble of streets, as well as minimize disputes over who owns what lot. A few historical cities like Paris were able to build grid layouts only after a major disaster provided the open space in which to build in a grid.
City planners knew about the benefits of a grid layout for a city, but rarely did they have the opportunity to plan cities to be built from the ground up per such a plan. The founding of the American colonies provided just such an opportunity.
The Oglethorpe Plan
The Oglethorpe plan was the municipal plan for Savannah, Georgia, to build a city laid out in a grid pattern. Not only were streets laid out in a grid for the commercial center, but the Oglethorpe plan contained a number of similar, connected neighborhoods.
The Oglethorpe plan was unique in a number of respects. Not only are there residential and commercial buildings in close proximity to each other, but Oglethorpe planned for multiple city squares and gardens, making Savannah, Georgia the first colonial town designed from the start with open space in mind. The Oglethorpe plan was designed as a large grid with plans for future expansion to repeat the same pattern, akin to a copy and paste of a successful city block onto a new, empty area.
The oldest known draft of the Oglethorpe plan was created in 1734.
Details of the Oglethrope Plan
The basic unit of each section was a ward, 600 feet north to south and between 540 to 600 feet east to west. Each of these wards had open space, originally planned to be garden lots. Savannah was the only major colonial city designed to have green space / garden space like this available to every resident in the city. This resulted in eight blocks to each ward, with everyone in walking distance of garden allotments.
Large, wide avenues connected the wards in a city-wide grid pattern. The streets were only interrupted by periodic squares to facilitate pedestrian traffic.
Within blocks were a variety of lot sizes, from sixty feet wide for larger houses or businesses to twenty to thirty feet wide for a then averaged sized house. The lots were large enough for a variety of uses but none so large that anyone in the city could build a mansion; this was intentional and in line with the utopian egalitarian ideals of Mr. Oglethorpe.
Civic duties were allocated to each ward from the start. Each ward had a chosen leader, a tythingman, and other tythingmen who acted as guards for the ward.
Planning for the Future
The Oglethorpe Plan was so successful that it was continued long after the colony of Georgia became part of the United States. Savannah continued expanding using the Oglethorpe plan until the mid-1900s and a total of 28 wards had been created. Around 21 Oglethorpe plan squares remain today.
The Oglethorpe Plan was copied to create a 500 acre neighborhood in St. Laurent, Quebec in 1993.