UNIT INDEX

    What does 21 kilometres look like?

    13-minute drive at 100 km/h

    How long is 21 kilometres?

    Rather than leaving 21 kilometres as an abstract number, these examples translate it into familiar scale.

    21-Kilometre Distance Comparisons

    • 21 kilometres is about 6% of the London to Paris.

      Its published measurement is 343.56 kilometres; the ratio is calculated from that figure.

      Source: GeoNames geographic coordinates

    • For scale, 21 kilometres is about 6% of the Paris to London.

      Its published measurement is 343.56 kilometres; the ratio is calculated from that figure.

      Source: GeoNames geographic coordinates

    • Measured against the Amsterdam to London, 21 kilometres spans about 6% of that reference.

      Its published measurement is 357.89 kilometres; the ratio is calculated from that figure.

      Source: GeoNames geographic coordinates

    • For scale, 21 kilometres is about 6% of the London to Amsterdam.

      Using the source measurement of 357.89 kilometres, this comparison puts the target at 6% of it.

      Source: GeoNames geographic coordinates

    • 21 kilometres is about 2.1 times the standard 10-kilometre road race.

      The comparison uses the published dimension, converted into the same unit before the proportion is calculated.

      Source: World Athletics

    • Measured against the 1,500-metre athletics event, 21 kilometres spans about 14 times that reference.

      Its published measurement is 1.5 kilometres; the ratio is calculated from that figure.

      Source: World Athletics

    • Measured against the Rio de Janeiro to São Paulo, 21 kilometres spans about 6% of that reference.

      The comparison uses the published dimension, converted into the same unit before the proportion is calculated.

      Source: GeoNames geographic coordinates

    • 21 kilometres is approximately 13 miles.

      Using the exact conversion that 1 kilometre equals exactly 0.6213711922 miles, the unrounded result is 13.049 miles.

    Reference measurements are rounded where appropriate, and naturally variable objects are described as approximate, typical, or maximum sizes.