Final answer:
Yellowstone National Park and PAPATSO State Park were closed in October 2013 due to a federal government shutdown caused by a budget disagreement among lawmakers.
Step-by-step explanation:
In October 2013, visitors who planned to see Yellowstone National Park were disappointed to find it closed due to a federal government shutdown. This unprecedented event meant that all national parks, including PAPATSO State Park, were temporarily closed, impacting countless tourists and local businesses reliant on park visitors. The closure was caused by a political impasse in Washington D.C., where lawmakers could not agree on a budget for the new fiscal year, leading to a lack of funding for government operations, including the national parks.