Integrated Civics — Geography · Question 128 of 128
What is the name of the longest river in the United States?
Practice answer: The Missouri River
Why this is the answer
The Missouri River is generally recognized as the longest river in the United States. The Mississippi River is the other river named among the country's two longest.
On the 2026 citizenship test, a USCIS officer asks up to 20 questions from the official 128-question pool — answering 12 correctly passes.
Study translations and question index
Practice index: 128. This is not the official 2025 syllabus question number. Translation indices share the same practice ID and answer-option order.
Español — practice:128:es
¿Cuál es el nombre del río más largo de los Estados Unidos?
El río Misuri
العربية — practice:128:ar
ما اسم أطول نهر في الولايات المتحدة؟
نهر ميزوري
Official syllabus and legal sources
M-1778 (09/25) — 2025 USCIS syllabus. Retrieved 2026-10-15. Check current USCIS answers.
- 8 U.S.C. § 1423 — English, history and civics requirements
- 8 C.F.R. § 312.2 — Knowledge of history and government
These laws establish testing requirements; they are not individual legal advice or a citation for every historical answer. Practice questions and study translations are editorial learning aids, not official USCIS translations. Confirm the test version that applies to your filing date.
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