The original fifty vara lot “was a unit designed to accommodate the homesteads, gardens, and outlying ranchlands that the Mexican government had thought each family required, . . . it was far larger than the typical American urban lot.” (Sandweiss 1993: 57) Thus, as the city expanded as an urbanized place, almost every original fifty vara lot was subdivided, initially into three to six lots, each more suitable for a city house or a rowhouse than for a house surrounded by a garden and farm animals. It was in the process of subdividing the fifty vara lots that the alleys were created. According to Nancy Olmsted, “in the 1880s some [of] these very small alleys were only 6 feet across — others were up to 20 feet in width.” (Bloomfield, et al. 1982: 81) Later, most of the narrowest alleys were widened. With the Gold Rush, San Francisco’s population boomed, earning it the description “instant city.” While the new population was concentrated around Yerba Buena Cove and Portsmouth Square, substantial development also took place in the future North Beach district in a short period of time. From little or no development at the time the grid was laid out, a map published by the U.S. Coast Survey in 1853 showed substantial development in the area. This development was heaviest between Broadway and Washington Square, but there were at least a few houses in every block that would later be considered part of North Beach (Woodbridge 2006: 46).