The town has been in heated competition for gambling revenue with its neighbor Central City since casinos opened in both towns in 1991. Development of the area down Clear Creek from the historic Black Hawk townsite lining State Highway 119 has flourished. Gamblers from Denver pass the Blackhawk casinos before they arrive at Central City, and, as a result, Black Hawk has realized much more revenue from gambling than Central City. Gambling in Black Hawk also benefits from less restrictive zoning codes; while Central City until recently limited building heights to to preserve the historic character of the town, Black Hawk has no such limits. In an attempt to close the competitive gap, Central City built the Central City Parkway from Interstate 70 near Idaho Springs as an alternative route, leading guests first to Central City, and then to Black Hawk. The Central City Parkway opened November 19, 2004. However, Black Hawk continues to have three times the number of casinos, and generates more than seven times the gambling revenue that Central City does.