60 degrees north latitude
The 42nd parallel forms the southern boundary of Idaho. It marks the border between Idaho and Nevada as well as a portion of the border between Idaho and Oregon.
The two states that have borders ending at 40 degrees north latitude are Colorado and Nebraska. This latitude line forms part of the boundary between these two states in the central United States. Additionally, it also marks the northern border of Kansas to the south.
The only state with part of its boundary defined by the arc of a perfect circle is Wyoming. The eastern boundary of Wyoming follows the 42nd parallel north latitude line, which forms part of a perfect circle around the Earth.
Mid-latitude cyclones typically produce both a cold front and a warm front. These will usually merge to form an occluded front.
Spain is the only country to border Portugal to the east.
The 42nd parallel forms the southern boundary of Idaho. It marks the border between Idaho and Nevada as well as a portion of the border between Idaho and Oregon.
The Potomac river
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The southern half of the eastern boundary of Alabama is the Chattahoochee River.
The Mediterranean Sea
The parallel of latitude approximately 66°33′ north. It forms the boundary between the North Temperate and North Frigid zones.
The Atlantic Ocean forms the eastern boundary of the Southeast, while the Gulf of Mexico forms the southern boundary.
Baffin Bay forms a natural boundary between Greenland (an autonomous territory of Denmark) and Baffin Island (part of the Canadian territory of Nunavut).
The Ohio River forms Ohio's southern border.
Most of the northern boundary is formed by the Alps. However, on the Iberian Peninsula, the Pyrenees form another northern border of Southern Europe.
Both Chile and Argentina, close to Antarctica.
Ohio River