Reading Ordnance Survey map symbols
Geography · Key Stage 3 · The School
Why symbols instead of words
Writing "public house" next to every pub on a busy map would bury the map in text and make it unreadable. A single small symbol takes almost no space, so a map can show hundreds of features clearly. The trade-off is that you must learn what each symbol means — which is exactly what the KEY at the edge of every OS map is for.
Categories of symbol
Symbols group into families. BLACK symbols mark buildings and features: churches, schools, public houses. BLUE marks water: rivers, lakes, marsh. GREEN marks woodland and open access land. BROWN marks relief: contour lines and spot heights. Orange and red mark roads by their importance. Learning the families first, rather than memorising every symbol at once, makes an unfamiliar one easier to guess.
The details that matter
Two similar symbols can mean genuinely different things. A church with a tower is a different symbol from a church with a spire, because a walker navigating by sight can actually see which one they are looking at. A public footpath is shown differently from a public bridleway, because only one of them permits a bicycle or a horse. These are not decorative choices — each difference is information someone genuinely needs.
Look at a stretch of OS map with no place names read yet. Blue lines show a river crossed by two bridges. Green shading marks a wood on the eastern bank. Brown contour lines, close together near the river and spreading out further away, show a steep bank flattening into a gentle valley. A dotted orange line is a footpath running along the western bank, and a black cross-topped symbol marks a church with a tower near where the path meets a road. Before reading a single word of text, the shape of a real walk is already visible: cross a bridge, follow the riverside path past the wood, climb gently, reach the church. That is what the symbols are actually for.