Milestone

"Milemarker" redirects here. For the American post-hardcore band, see Milemarker (band).

For other uses, see Milestone (disambiguation).

A milemarker on the National Road giving distances from many places

A milestone or kilometre sign is one of a series of numbered markers placed along a road or boundary at regular intervals, typically at the side of the road or in a median. Milestones are constructed both to reassure the traveller that the proper path is being followed and to indicate distance travelled, or the remaining distance to the desired destination. They are alternatively known as a mile marker, milepost, or mile post (sometimes abbreviated MP), notably in the United States.

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. i.e. "an accident occurred at the 13.45km mark" even if the road is only marked with a stone once every 10km.

The historical term milestone (from the Latin milliarium) is still used today, even though the "stones" are typically metal signs. More closely spaced signs, with fractional numbers, and signs along a railway or beach also occur.

Slate milestone near Bangor, Wales

In Europe the distance measured typically starts at a city or town, as many roads were named for the towns at either end. In the United Kingdom, a plaque near the Eleanor cross at Charing Cross in London is the reference point from which distances to other towns and cities are measured. In the US Interstate highway system the numbers usually measure the distance to the southern or western state line, while other highways use the county line as the benchmark. Often, the exits are numbered according to the nearest milepost, known as the mile-log system. Some historic and scenic routes use mileposts to mark points of interest, such as along the Blue Ridge Parkway in North Carolina and Virginia, and the Overseas Highway of the Florida Keys.

Zero Milestone in Washington, D.C.

Milestones were originally stone (granite or marble or whatever local stone was available) obelisks and later concrete posts. They were widely used by the Roman Empire roadbuilders, an important part of any Roman road network when the distance travelled per day was only a few miles in some cases. The first Roman milestones appeared on the Appian way. At the centre of Rome the "Golden Milestone" (actually bronze) was erected that marked the metaphorical 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.

Spanish ten kilometres marker on highways.

Railway mileposts

In 1845 the Railways Clauses Consolidation Act was passed compelling the UK railway companies to provide their passengers with a means of determining the distance traveled (fares were set by distance at this time). Section 94 states:

The company shall cause the length of the railway to be measured, and milestones, posts, or other conspicuous objects to be set up and maintained along the whole line thereof, at the distance of one quarter of a mile from each other, with numbers or marks inscribed thereon denoting such distances.

Similar laws applied in other countries. On the modern railway these historical markers are still used as infrastructure reference points. At many points the distances shown on the markers are based upon points no longer on the network, for example measured via a closed line or from a junction which has subsequently been moved. Whole mileposts are usually supplemented by half and quarter posts. Structure signs often include the mileage to a fair degree of precision: in the UK a chain is the usual accuracy. In the US and Canada, however, miles are "decimalized", so that, for example, there may be a "milepost 4.83."

In metricated areas the equivalent is the pointe kilometric, or pk.

Milestones on Indian highways

A milestone near Haridwar on an Indian highway

Milestones on Indian highways typically have white background with a yellow (yellow top signifies a national highway) or green top (green top signifies a state highway). The names of cities and distances are painted in black. The names of nearest towns and cities are written along with distance in kilometers. On undivided highways, both sides of the milestones are used, telling the distance to the nearest cities in each direction. The head of the milestone has the highway number written on it. The side of the milestone has a number which is the sum of distances of two nearest cities in each direction from the milestone.

Milestones on boundaries

Surveyors place milestones to mark the boundaries between the jurisdictions that borders separate. A series of such boundary markers exists at one mile intervals along the borders of the District of Columbia in the United States.

See also

• Boundary marker
• Milestone (Project management)
• Milepost equation
• Reassurance marker — a roadsign with the route number, but no distance

Gallery

UK Mile stones

• 
  A milestone on the old route of the A148, close to the center of Holt. Note the measurement in furlongs.
• 
  The other side of the same milestone in Holt.
• 
  A milestone on the A148 in the village of High Kelling.
• 
  The other side of the same milestone in High Kelling.
• 
  A milestone on the A140 in Horsham St. Faith.

External links

• Milepost Society UK
• Mileposts and milestones on the Leeds Liverpool Canal
• Article in Smith's Dictionary of Greek and Roman Antiquities with further links, including to a photograph of a Roman milestone in Orvieto
• Inventory of Roman milestones in France (in French)
• Section 2D.46 of the U.S. Manual on Uniform Traffic Control Devices