Cahokia, Illinois was the largest and most important urban settlement of the Mississippian culture and is the largest pre-Columbian archaeological site north of Mexico. The society reached its peak between 1050 and 1150, when it was estimated to have a population of 10,000 to 20,000 people. The site includes some 120 mounds, including the Monks Mound (pictured), the largest prehistoric earthen structure in the Americas. The site also includes the Woodhenge, believed to serve as an astronomical observatory. The layout of the settlement demonstrates the existence of political and economic hierarchy of the society. Before today's survey, were you aware of this ancient civilization?

The Great Smoky Mountains National Park is a refuge of the flora and fauna from the diverse Arcto-Tertiary Geoflora era that has survived the Quaternary glaciations. It is a biodiversity hotspot, containing over 3,500 plant species and numerous animal species, including one of the world's greatest variety of salamanders, in particular lungless salamanders. Have you ever been to the Great Smoky mountains?

The 16th-century fortress La Fortaleza (pictured) and the later fortifications of Castillo San Felipe del Morro, Castillo de San Cristóbal, El Cañuelo, and the City Wall of San Juan, dating between the 16th and 20th centuries, were constructed by the Europeans to protect the bay and the city of San Juan, Puerto Rico. They incorporate architectural elements of Italian Renaissance, Baroque, and French Enlightenment, and they demonstrate the evolution and adaptation of European military architecture to the setting of a Caribbean island. A minor boundary modification took place in 2016. Would you tour these old forts if you were vacationing in San Juan, Puerto Rico?

The Statue of Liberty, inaugurated in 1886, was a gift from France to commemorate the centenary of American independence. It was designed by Frédéric Bartholdi in collaboration with engineer Gustave Eiffel, and its construction, with a metal frame supporting the skin, use of concrete at the base, and electricity to power the torch, was seen as a harbinger of a new era. The statue is located at the entrance to the New York City harbor where it has welcomed millions of migrants. It symbolizes ideas such as liberty, peace, and human rights. Do you feel that the Statue of Liberty is still relevant?