List of areas in the United States National Park System
National preserves

Name
Location
Area (2017)
Aniakchak National Monument and Preserve
Alaska
464,117.93 acres (1,878.2186 km2)
Bering Land Bridge National Preserve
Alaska
2,697,391.01 acres (10,915.9541 km2)
Big Cypress National Preserve
Florida
720,564.01 acres (2,916.0191 km2)
Big Thicket National Preserve
Texas
113,121.96 acres (457.7883 km2)
Craters of the Moon National Monument and Preserve
Idaho
698,939.69 acres (2,828.5086 km2)
Denali National Park and Preserve
Alaska
1,334,117.80 acres (5,398.9832 km2)
Gates of the Arctic National Park and Preserve
Alaska
948,608.07 acres (3,838.8807 km2)
Glacier Bay National Park and Preserve
Alaska
58,406.00 acres (236.3607 km2)
Great Sand Dunes National Park and Preserve
Colorado
41,686.00 acres (168.6973 km2)
Jean Lafitte National Historical Park and Preserve
Louisiana
22,420.86 acres (90.7340 km2)
Katmai National Park and Preserve
Alaska
418,698.80 acres (1,694.4139 km2)
Lake Clark National Park and Preserve
Alaska
1,410,293.68 acres (5,707.2560 km2)
Little River Canyon National Preserve
Alabama
15,288.58 acres (61.8707 km2)
Mojave National Preserve
California
1,545,685.49 acres (6,255.1673 km2)
Noatak National Preserve
Alaska
6,587,071.39 acres (26,656.9322 km2)
Oregon Caves National Monument and Preserve
Oregon
4,554.03 acres (18.4295 km2)
Tallgrass Prairie National Preserve
Kansas
10,882.67 acres (44.0406 km2)
Timucuan Ecological and Historic Preserve
Florida
46,262.67 acres (187.2184 km2)
Valles Caldera National Preserve
New Mexico
89,766.09 acres (363.2705 km2)
Wrangell-St. Elias National Park and Preserve
Alaska
4,852,644.52 acres (19,637.9556 km2)
Yukon-Charley Rivers National Preserve
Alaska
2,526,512.44 acres (10,224.4331 km2)

Question: What national preserves have "big" in their name?
Answer: The Big Cypress and Big Thicket National Preserve are the national preserves in the United States National Park System.