1.0Gizmodo Australiahttps://gizmodo.com.auSarah Zhanghttps://gizmodo.com.au/author/sarahzhang-usa/rich600338<blockquote class="wp-embedded-content" data-secret="BoaBssDg0l"><a href="https://gizmodo.com.au/2014/10/an-arizona-highway-has-used-the-metric-system-since-the-1980s/">An Arizona Highway Has Used The Metric System Since The 1980s</a></blockquote><iframe sandbox="allow-scripts" security="restricted" src="https://gizmodo.com.au/2014/10/an-arizona-highway-has-used-the-metric-system-since-the-1980s/embed/#?secret=BoaBssDg0l" width="600" height="338" title="“An Arizona Highway Has Used The Metric System Since The 1980s” — Gizmodo Australia" data-secret="BoaBssDg0l" frameborder="0" marginwidth="0" marginheight="0" scrolling="no" class="wp-embedded-content"></iframe><script> /*! This file is auto-generated */ !function(d,l){"use strict";l.querySelector&&d.addEventListener&&"undefined"!=typeof URL&&(d.wp=d.wp||{},d.wp.receiveEmbedMessage||(d.wp.receiveEmbedMessage=function(e){var t=e.data;if((t||t.secret||t.message||t.value)&&!/[^a-zA-Z0-9]/.test(t.secret)){for(var s,r,n,a=l.querySelectorAll('iframe[data-secret="'+t.secret+'"]'),o=l.querySelectorAll('blockquote[data-secret="'+t.secret+'"]'),c=new RegExp("^https?:$","i"),i=0;i<o.length;i++)o[i].style.display="none";for(i=0;i<a.length;i++)s=a[i],e.source===s.contentWindow&&(s.removeAttribute("style"),"height"===t.message?(1e3<(r=parseInt(t.value,10))?r=1e3:~~r<200&&(r=200),s.height=r):"link"===t.message&&(r=new URL(s.getAttribute("src")),n=new URL(t.value),c.test(n.protocol))&&n.host===r.host&&l.activeElement===s&&(d.top.location.href=t.value))}},d.addEventListener("message",d.wp.receiveEmbedMessage,!1),l.addEventListener("DOMContentLoaded",function(){for(var e,t,s=l.querySelectorAll("iframe.wp-embedded-content"),r=0;r<s.length;r++)(t=(e=s[r]).getAttribute("data-secret"))||(t=Math.random().toString(36).substring(2,12),e.src+="#?secret="+t,e.setAttribute("data-secret",t)),e.contentWindow.postMessage({message:"ready",secret:t},"*")},!1)))}(window,document); </script> https://gizmodo.com.au/wp-content/uploads/2014/10/08/ffgkytyo5ju0tfx759er.jpg?quality=75640290Who doesn’t like a maths pop quiz when driving down to the Mexican border? If you turn onto Interstate 19, which runs 101km from Tucson, Arizona, down to Mexico, the road signs suddenly change to metric units. Interstate 19 is a relic from a more optimistic era, when we believed all of the US could […]