There have been 3 Black Wall Streets:
These were the most successful African-American business districts.
The most famous and successful Black Wall Street was that of Tulsa, OK in the early 1920's before it was burned down in the Tulsa "Race Riot." This black wall street is the subject of the #RememberBlackWallStreet movement.
These Black Wall Streets can be said to challenge the notion that African-Americans cannot build successful cities.