2,000 billions ways of tying up your shoelaces!
Mathematically speaking, given a classic shoe with twelve eyelets (six per side), the number of ways of tying up its shoelace is no fewer than 2 trillion. Clearer still: 2,000 billions! More or less, because the exact number (which is still very high), is 1,961,990,553,600.
Obviously it is not necessary to know them all. Only the bravest dare go beyond the three or four most common ways of tying laces (but if you really are in the mood for it here is a guide that teaches you 43 different ways of lacing up a shoe).
The Areni-1 shoe is a 5,500-year-old leather shoe that was found in 2008 in excellent condition in Armenia. It has laces.
Shoelaces are currently produced using a broad range of materials. In addition to leather and natural fibres (such as cotton, hemp and jute) there are synthetic fibres.
Shoelaces come in three main shapes (with a square, round or flat cross-section). Fabric shoelaces are usually strengthened with metal or plastic aglets, which makes it easier to thread them through the eyelets and prevents fraying.
Shoelaces can be treated with wax or silicone to increase friction and reduce the chances of them coming accidentally undone.
The length of a shoelace depends on various factors, such as the number of eyelets, the distance between eyelets, the kind of knot used to tie the laces and the remaining length of the shoelace. A shoe with two eyelets requires a shoelace that is approximately 45 cm long – a shoe with 16 eyelets will require one that is 200 cm long.