Yes. The parks need visitors, and gateway communities—towns and businesses that depend on park tourism—need your support.

Earth Day also falls during National Park Week. Celebrated for 55 years, one billion people in 193 countries host events and celebrations of the planet, its resources and our commitment to protect it. Many of our national parks will have special Earth Day demonstrations of earth science or discussions of the latest environmental concerns.

Firings, buyouts and a lack of seasonal workers could mean jammed roads, closed campgrounds, limited hours and more. What you need to know before traveling to 10 popular parks.