Power line symbol
A thin line with dots at intervals is a power transmission line; the dots are poles and a small square is a tower.
Easily confused with
How to read it
The USGS symbol sheet draws a power transmission line with symbols for a pole and a tower, and a telephone line with a different, dashed symbol. Natural Resources Canada prints power transmission lines in black with buildings and railways.
Also searched as: electricity transmission line, line with dots on a map, power transmission line, pylons on a map.
These pages describe what each symbol on a map shows. They are not navigation instructions: the map’s own legend says what each of its symbols means, and symbols differ between map series and editions.
Differences by country
On the Ordnance Survey’s Landranger maps an electricity transmission line is drawn with its pylons “shown at standard spacing”, so the pylon symbols do not mark where each pylon stands.
Look-alikes
Short ticks across a line are a Railroad symbol. A plain dashed black line can be a Trail symbol or a pipeline; the legend says which.
Read next
- Next in Topographic map symbolsIntermittent stream symbolA blue line of dashes and dots is an intermittent stream: one that flows only part of the year. A solid blue line is a perennial stream that flows all year.
- The same shape in African flagsFlag of AngolaAngola’s flag is red over black with a yellow emblem in the centre: part of a cogwheel, a machete and a five-pointed star. Its constitution says the red is the blood shed by Angolans under colonial oppression, in the liberation struggle and in defence of the country, and the black is the African continent; the cogwheel stands for workers and industry, the machete for peasants, farming and the armed struggle, the star for international solidarity and progress, and their yellow for the country’s wealth.
More topographic map symbols
The same shape elsewhere
Browse symbols drawn with lines or squares and rectangles.
Sources
- Topographic Map Symbols, USGS General Information Product (first posted 2005), U.S. Geological Survey, Transmission lines and pipelines
- Topographic Maps: The Basics, Centre for Topographic Information guide, Natural Resources Canada, What do the colours mean?
- OS Landranger map legend (1:50 000), Legend, January 2015, Ordnance Survey, General features
Researched, edited and approved by Rory Hansen before publishing. Last reviewed October 9, 2026. How we research
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