In rural Finland you'll often see 100 house numbers per kilometer. Alternating even & odd, you'd get a number every 20 meters, which is more than sufficient. I'

In rural Finland you'll often see 100 house numbers per kilometer. Alternating even & odd, you'd get a number every 20 meters, which is more than sufficient. I'd think this is really handy for emergency services, when people don't bother to put up house numbers on dirt roads.