adjacent states
21United States Census — The United States Census is a decennial census mandated by the United States Constitution. [, Article 1, Section 2: The actual Enumeration shall be made within three Years after the first Meeting of the Congress of the United States, and within… …
22Rail transportation in the United States — Rail transport Operations Track Maintenance High speed Gauge Stations …
23United States Holocaust Memorial Museum — Coordinates: 38°53′13″N 77°01′59″W / 38.8869924°N 77.033021°W / 38.8869924; 77.033021 …
24United States Marine Corps Force Reconnaissance — Not to be confused with Marine Division Reconnaissance. Main article: United States Marine Air Ground Task Force Reconnaissance Marine Force Reconnaissance The insignia of Force Recon …
25Digital television transition in the United States — Further information: Digital television transition The DTV (an abbreviation of digital television, also called digital broadcast) transition in the United States was the switchover from analog (the traditional method of transmitting television… …
26United States Navy Memorial — IUCN Category V (Protected Landscape/Seascape) …
27Etiquette in Canada and the United States — Etiquette rules are not uniform in North America, varying among the very diverse societies which exist in both the United States and Canada. Etiquette rules are not simply a description of “cultural norms” and should not be considered a summary… …
28Canada – United States border — The Canada – United States border is the international border between Canada and the United States. Officially known as the International Boundary, it is the longest common border in the world, and is unmilitarized. The terrestrial boundary… …
29List of largest shopping malls in the United States — This is a list of the largest shopping malls in the United States of America based on total square feet of retail space (gross leasable area). The list is based in part on information gathered by the Department of American Studies at Eastern… …
30United States Post Office and Court House (Davenport, Iowa) — United States Post Office and Court House U.S. National Register of Historic Places …