The five previous addressing sections of Portland, which were colloquially known as quadrants despite there being five, have developed distinctive identities, with mild cultural differences and friendly rivalries between their residents, especially between those who live east of the Willamette River versus west of the river. Portland's addressing sections are North, Northwest, Northeast, South, Southeast, and Southwest (which includes downtown Portland). The Willamette River divides the city into east and west while Burnside Street, which traverses the entire city lengthwise, divides the north and south. North Portland consists of the peninsula formed by the Willamette and Columbia Rivers, with N Williams Ave serving as its eastern boundary. All addresses and streets within the city are prefixed by N, NW, NE, SW or SE with the exception of Burnside Street, which is prefixed with W or E. Starting on May 1, 2020, former Southwest prefix addresses with house numbers on east–west streets leading with zero dropped the zero and the street prefix on all streets (including north–south streets) converted from Southwest to South. For example, the current address of 246 S. California St. was changed from 0246 SW California St. and the current address of 4310 S. Macadam Ave. was converted from 4310 SW Macadam Ave. effective on May 1, 2020.