Canada and the United States.
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what makes you think it is undefended
The United States and Canada share the world's longest undefended border, stretching over 5,500 miles. The border is known as the "Peace Arch Border," symbolizing the peaceful relationship between the two countries.
The Ocean Ridge (also known as Mid-ocean ridge), which runs more than 40,000 miles on the sea floor of five oceans is the longest mountain chain in the world. The longest mountain range on dry land is the Andes, which stretch 4300 miles through seven countries in South America.
The largest countries in the world by land area are: Russia: 17,098,250 square kilometers Canada: 9,984,670 square kilometers United States: 9,834,000 square kilometers These rankings are subject to change based on various factors like border disputes or changes in geographical data.
China and Australia are the world's largest producers of gold.
The world's longest rift valley is the East African Rift, which stretches over 3,000 miles from the Afar Triple Junction in Ethiopia to Mozambique in southeastern Africa. It is a tectonic plate boundary where the African Plate is splitting into two separate plates, creating a diverse landscape of mountains, lakes, and valleys.
The world's farthest north countries are Norway, Iceland, Finland, Sweden, and Russia. Each of these countries has territory located within the Arctic Circle, which is the northernmost circle of latitude on Earth.
Between Canada and the US. ================================================================================ An open border is one that allows unrestricted entry and exit. The border between Canada and the US has been described as the world's longest "undefended" border, but it is not an "open" border. Even the "undefended" concept of the Canada-US border is now being questioned.
The Amazon River in South America is the longest river in the world. Tennessee does not border it.
worlds longest toenailes
The worlds longest road bridge is in China
The Worlds Longest limo is 100 feet long ( 30 meters )
The Amazon River is the second longest in the worlds, is in South America and runs through countries - Peru, Colombia, Brazil, Bolivia, Venezuela, Ecuador and Guyana.
Hebesberger UT (Rossleithen) has the longest tunnel
The longest nipple had 4 or 5 cm
Answer
Australia.
The worlds longest river, the Nile, is in Africa
One of the worlds longest rivers that begins with the letter n is the Nile. This river is in Egypt.