Main Street
From Conservapedia
Main Street, named after the typical central street in many towns, is used in American English to indicate typical small cities or towns, as opposed to a large metropolis like New York, Chicago, Los Angeles or Dallas.
Main Street often stands in opposition to Wall Street, which represents major national businesses, such as big banks, giant corporations, or the New York Stock Exchange (which is located on Wall Street in New York City).
In political terms in the U.S., Main Street represents locally owned and operated businesses, as opposed to national corporations. Peoria, Illinois is a mid-sized Midwestern city often associated with the proverbial "Main Street."
Its British equivalent is High Street.