standard metre

The Metre etalon on Paris's Place Vendome is a marble bar set flush into a building's wall, one of the last publicly accessible standard meters from the French Revolution. Between 1796 and 1797 the French Republic installed sixteen such standards at busy spots so citizens could learn the new unit replacing the royal ell, toise, and fathom. Only two have survived: this one and a second on Rue de Vaugirard 36. The stone is exactly one meter long and sits unobtrusively in the arcade of a ministry building at number 13. Tourists usually walk past without noticing; if you know to look, you're standing right in front of a piece of scientific history.