In 2002, the economic impact of tourism within the state reached about $9.1 billion dollars, including the support of over 164,000 travel-related jobs. This represented a 5.2% increase in travel expenditures over 2001. The increase has been attributed, in part, to the impact of the Kentucky Tourism Development Act of 1996, which provides incentives for new or expanding tourist-related businesses.
One of the state's top tourist attractions is Mammoth Cave National Park, which contains an estimated 150 mi (241 km) of underground passages. Other units of the national park system in Kentucky include a re-creation of Abraham Lincoln's birthplace in Hodgenville and Cumberland Gap National Historical Park, which extends into Tennessee and Virginia.
The state operates 15 resort parks (13 of them year round). The state also operates 15 recreational parks and 9 shrines. Breaks Interstate Park, on the Kentucky-Virginia border, is noted for the Russell Fork River Canyon, which is 1,600 feet (488 meters) deep; the park is supported equally by the two states.
In 1979, the Kentucky Horse Park opened in Lexington. The Kentucky State Fair is held every August at Louisville.