Direction, position, or indication sign

A direction sign, more fully defined as a direction, position, or indication sign by the Vienna Convention on Road Signs and Signals, is any road sign used primarily to give information about the location of either the driver or possible destinations, and are considered a subset of the informative signs group. Direction signs are far more varied internationally than other classes of sign, as the Vienna Convention does not specify sizes, colours, symbols or positions of such signs.

Direction signs are the oldest type of road sign; Plutarch writes about milestones being placed in the 3rd century BC, while some fingerposts in the United Kingdom date back to at least the 1690s. However, it was not until the invention of the motor car at the turn of the 20th century that modern direction signs evolved, with fewer words and clear design allowing them to be read at speed.

The first direction signs were milestones on the Roman road network; finding one's location on the long, straight roads was difficult, and hence, large stones were placed at intervals along the roads, giving the distance in Roman miles to nearby major cities, and usually to the capitals of major provinces. As most Roman roads diverged from Rome, one of the numbers was usually the distance to the Milliarium Aureum, a large golden milestone in the centre of Rome, although sometimes other stones, such as the London Stone, were used in places where measuring distances from Rome was impossible or not useful.

The use of milestones continued following the decline of the Roman Empire. However, as trading between towns and regions increased, milestones were found to be inconvenient for giving directions at crossroads. As a result, the fingerpost developed. Erected by local parishes, fingerposts were easier to read from horseback and were cheaper to make. With the development of the turnpike and the stagecoach, the Turnpike Roads Act 1773 was passed, making signposting compulsory to allow the riders to judge their speed and prevent them from becoming lost. Similar signs were developed in other countries and remained in use until the early-20th century, when development of the motor car made the small and often wordy signs impractical.

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