Travelers to La Paz, Bolivia, often become ill the moment they arrive. Why? La Paz is 11,900 feet above sea level - the highest metropolis in the world. People with heart or bronchial conditions are advised to avoid it, and even those in good health often experience altitude sickness.

Antarctica is the only continent that does not have any land areas below sea level.

The states of Arizona and Hawaii have never adopted Daylight Savings Time. Neither have Puerto Rico, the Virgin Islands, or American Samoa.

Before 1903, Panama was part of South America. After declaring independence from Colombia in its 50th revolution, Panama chose to associate itself with North America. The decision was political and strategic - and remains in place today.

Juneau, Alaska, covers more land area than any other city in the Western Hemisphere. After consolidating surrounding districts in 1977, the city now spans 3,108 square miles - including 1,476 of dry land, 928 of icecap, and 704 of water. By comparison, Jacksonville, Florida has 840 square miles, and New York City has only 320.

Of the twenty-five highest mountains on Earth, nineteen are in the Himalayas.

The tallest mountain in the British Isles, Ben Nevis in Scotland, rises just 4,406 feet. In many other countries, a "mountain" of this size would barely qualify as a large hill.

The needle of a compass doesn't point to true north. Instead, it aligns with magnetic north, which varies slightly from geographic north. This "variation of the compass" is well known among navigators and must be accounted for in precise calculations.

On a clear day, five U.S. states are visible from the top of the Empire State Building: New York, New Jersey, Connecticut, Massachusetts, and Pennsylvania.

More than 90% of the ocean remains unexplored, and its full depths are still largely a mystery to science.

Bangladesh and the U.S. state of Wisconsin cover roughly the same land area - but Bangladesh ranks among the top 10 most populous countries in the world.

When Secretary of State William Seward bought Alaska in 1867 for $7.2 million, he was mocked for the decision. The press called it "Seward's Icebox" and "Walrussia." He named it "Alakshah," from the Aleut word meaning "great country."

If the Nile River were stretched across the United States, it would span roughly the distance between New York City and Los Angeles.

The Nile is the only major river that begins near the equator and flows into a temperate zone. Most rivers flow in the opposite direction due to climate and elevation factors.

Alaska has a sand desert along the Kobuk River with dunes that rise over 100 feet high - a surprising geographic feature for such a northern region.

Canada, the second-largest country in the world, has a land area of 3.85 million square miles. The Soviet Union (when it existed) spanned over 8.6 million square miles - more than double Canada's size.