### Kilometers

**Abbreviation/Symbol:**

- Km
- Slang: ‘k’ or ‘kays’ – spoken

**Unit of:**

- Length / distance

**Worldwide use:**

- The kilometre is used worldwide as a unit used for expressing distances between geographical locations on land, and in most countries is the official unit for this purpose. Primary exceptions are the United Kingdom and the United States of America, where the mile remains as standard.

**Definition:**

The kilometre is unit of length in the metric system equivalent to one thousand metres.

1Km is equivalent to 0.6214 miles.

**Origin:**

The metric, or decimal, system of weights and measures was adopted in France in 1795. Using the metre as the basis for length measurements, the system is now used officially across the globe, with a few notable exceptions.

**Common references:**

- The world’s tallest building, Burk Khalifa in Dubai, is 0.82984km tall.
- Niagara Falls, on the U.S.A./Canada border, is approximately 1Km across
- The peak of Mount Everest is 8.848Km above sea level.
- Paris in France is 878Km from Berlin in Germany, although you would have to make a journey of over 1050Km to travel from one to the other by land transport.
- The average distance from Earth to the Moon is 384,400Km.

**Usage context:**

The kilometre is most commonly used on road signs to denote the distance left to travel to a given location. It is also the most popular unit for describing the distance between two locations in a straight line (across the surface of the Earth).

**Component units:**

- 1 km = 1000m (metres)

**Multiples:**

- Units of length/distance in the metric scale are based on fractions or multiples of one metre, thus there are no official multiples of the kilometre.
- However, there are metric measurements of length/distance greater than a kilometre that can be expressed in terms of kilometres.
- A megameter = 1 million metres (or 10,000Km)
- A gigametre = 1 billion metres (or 1,000,000Km)