In the The first speed limit on record was set at 10 mph in 1865 in the United Kingdom. This 35 miles per hour sign came along over a century later, which means it's much easier to hang than the wood varieties that existed long ago. The black on white color scheme for regulatory signs is the norm in North America, Australia and New Zealand. Brown bears and giraffs can travel up to 35 mph, as can sneezes. For a giraffe a long run at that pace can cause a heart attack and giraffes are cool so don't chase them. In the words of Chen Stormstout, "Slow down."