Technisches Museum, Vienna, Austria (1 of 6)

This pretty much sums up the first couple of decades with cars. As always, it took quite some time to work out the kinks in the system. For example:

How do you mark pedestrian crossings? (First attempt to do so was in 1926, when cars had been in Vienna for at least twenty years. In 1910 Vienna had about 4000 cars.)
How many traffic signs should there be? (Drivers thought sixteen were far too many.)
...and so on...