Although some English colonial cities, such as Boston, had streets that adhered more to natural topography and happenstance, others, such as Savannah, Georgia, Baltimore, and Philadelphia had been built to the gridiron concept from the beginning Eldredge & Horenstein (2014), p. 110 A street map of Savannah in 1818 can be found in Ballon, p. 50 spndin Philadelphia's case, William Penn specified the city's orthogonal pattern when he founded it in 1682, although its 400 feet blocks turned out to be too large, encouraging the creation of intermediate streets, while James Oglethorpe's Savannah, with its significantly smaller blocks, was not conducive to large-scale development, restricting the city's economic influence.