For ten days this year, entrance fees at national parks will be waived.
The first free day is Jan. 16, Martin Luther King Day.
The free days are in place to celebrate the National Park Service's 100th anniversary.
There are 14 national parks in Texas alone.
The other dates:
February 20: Presidents' Day
April 15-16 and 22-23: Weekends of National Park Week
August 25: National Park Service Birthday
September 30: National Public Lands Day
November 11-12: Veterans Day Weekend