10 most difficult geography of the United States riddles A list of geography of the United States related questions that are most often answered incorrectly North America quiz What is the third longest river of the North America? (after Mississippi and Missouri)Yukon, having 1,979 mi (3,185 km), is just 223 miles shorter than Mississippi. Despite its length, there are only four vehicles-carrying bridges across the river.very hard 29% Rio GrandeRio Grande24%YukonYukon29%ColoradoColorado42%ArkansasArkansas3%Created by: globalquiz.org. Statistics based on 9825 answers in 2 languages »Alaska riddles » Why is White Sands Desert in New Mexico so purely white?It is gypsum. White Sands, having 442 total square kilometers of dune fields, is the world's largest surface deposit of gypsum. Unlike other desert sands, it is cool to the touch, due to the high rate of evaporation of surface moisture and the fact that the sands reflect, rather than absorb, the sun's rays.very hard 30% it is gypsumit is gypsum30%it is very fine grained sandit is very fine grained sand10%it iswhite quartzit iswhite quartz36%it is an optical illusionit is an optical illusion22%Created by: Debbie Fox. Statistics based on 13129 answers in 4 languages »soil riddles » What is the longest river in the United States?Missouri. The Missouri River is the longest river in North America. Having 2,341 mi (3,768 km), it is longer than the Mississippi (2,202 mi 3,544 km). When combined with the lower Mississippi River, it forms the world's third longest river system, after the Nile and Amazon.very hard 39% MississippiMississippi46%MissouriMissouri39%YukonYukon7%Rio GrandeRio Grande6%Created by: Shankar Kumar. Statistics based on 6065 answers in 4 languages »rivers of North America riddles » Which of the following North American rivers has the lowest discharge?Rio Grande is the fourth or fifth longest river system in North America, but it flows through arid and desert regions. The average discharge is just 82 m³/s (St Lawrence: 10100, Yukon: 6200, Colorado: 1200). It is also very variable, occasionally rising to over 10000 m³/s or dropping to 1 m³/s. During portions of 2001 and 2002 the mouth of the Rio Grande was blocked by a sandbar. hard 40% Rio GrandeRio Grande40%St LawrenceSt Lawrence23%YukonYukon19%ColoradoColorado16%Created by: Riho Ishii. Statistics based on 20521 answers in 2 languages »geography of Mexico riddles » What is the second most populous state in the USA? (after California)Texas. The 4 most populous states are California (38M), Texas (26M), New York (19M) and Florida (19M).hard 43% New YorkNew York31%FloridaFlorida16%IllinoisIllinois7%TexasTexas43%Created by: globalquiz.org. Statistics based on 14478 answers in 2 languages »geography of North America riddles » Which state of the USA is that?Washington. Such large and rocky mountains are found only on the west of the North America. This is a photo of Mount Rainier over Tacoma, Washington, USA.hard 45% New YorkNew York5%Rhode IslandRhode Island21%WashingtonWashington45%PennsylvaniaPennsylvania27%Created by: globalquiz.org. Statistics based on 17025 answers in 2 languages »mountains riddles » Where is New York?At point 1. The easily recognizable Long Island extends 118 miles (190 km) eastward from New York Harbor. It is both the longest and the largest island in the contiguous United States. hard 47% at point 1at point 147%at point 2at point 225%at point 3at point 317%at point 4at point 49%Created by: globalquiz.org. Statistics based on 25932 answers in 2 languages »New York riddles » Where is the capital of the United States?At point 2. The states of Maryland and Virginia each donated land to form the federal district with Washington.hard 49% at point 1at point 112%at point 2at point 249%at point 3at point 318%at point 4at point 419%Created by: globalquiz.org. Statistics based on 28464 answers in 2 languages »maps riddles » Where is Niagara Falls?At point 3. Located on the Niagara River, which drains Lake Erie into Lake Ontario, the combined falls form the highest flow rate of any waterfall in the world.hard 54% at point 1at point 19%at point 2at point 219%at point 3at point 354%at point 4at point 416%Created by: globalquiz.org. Statistics based on 18198 answers in 2 languages »waterfalls riddles » What is Santa Clara Valley better known as?Silicon Valley. The term Silicon Valley first appeared in the Electronic News newspaper in 1971. In 2006, Silicon Valley had 225,300 high-tech jobs.average 63% Black CanyonBlack Canyon6%Bryce CanyonBryce Canyon9%Silicon ValleySilicon Valley63%Death ValleyDeath Valley20%Created by: Kasia. Statistics based on 22362 answers in 2 languages »geographic names riddles » Play North America quiz and see all the questions.