Milestone

A milestone is one of a series of numbered markers placed along a road or boundary at intervals of one mile or occasionally, parts of a mile. They are typically located at the side of the road or in a median. They are alternatively known as mile markers, mileposts or mile posts (sometimes abbreviated MPs). Mileage is the distance along the road from a fixed commencement point.

Milestones are constructed to provide reference points along the road. This can be used to reassure travellers that the proper path is being followed, and to indicate either distance travelled or the remaining distance to a destination. Such references are also used to by maintenance engineers and emergency services to direct them to specific points where their presence is required. This term is sometimes used to denote a location on a road even if no physical sign is present. This is useful for accident reporting and other record keeping (e.g., "an accident occurred at the 13 mile mark" even if the road is only marked with a stone once every 10 miles).

Roman Empire

Milestones were originally stone obelisks – made from granite, marble, or whatever local stone was available – and later concrete posts. They were widely used by Roman Empire road builders and were an important part of any Roman road network: the distance travelled per day was only a few miles in some cases. Many Roman milestones only record the name of the reigning emperor without giving any placenames or distances.[1] The first Roman milestones appeared on the Appian way. At the centre of Rome, the "Golden Milestone" was erected to mark the presumed centre of the empire: this milestone has since been lost. The Golden Milestone inspired the Zero Milestone in Washington, D.C., intended as the point from which all road distances in the United States should be reckoned.

Byzantine Empire

A mile-marker monument, the Milion, was erected in the early 4th century AD in Constantinople. It served as the starting point for measurement of distances for all the roads leading to the cities of the Byzantine Empire, and had the same function as the Milliarium Aureum of Ancient Rome. The Milion survived intact until at least the late 15th century. Its fragments were discovered again in the late 1960s. A fragment is re-erected as a pillar.

Post Medieval Europe

In Europe, the distance measured typically starts at specified point within a city or town, as many roads were named for the towns at either end. For example in London, United Kingdom, a plaque near the Eleanor cross at Charing Cross is the reference point from which distances from London to other towns and cities are measured. In the UK, milestones are especially associated with former Turnpike roads.

Modern highways

The historical term milestone is still used today, even though the "stones" are typically metal signs and in most countries are based on metric rather than imperial units of measure. Also found today are more closely spaced signs containing fractional numbers, and signs along railways, beaches and canals.

For further reading see 'Roman roads'