That depends on what type of map you are referring to.
On a weather map it's usually part of a warm front.
On a road map they could be any type of road the cartographer specifies.
On a topographical map they could be elevation lines.
On the Washington Transit Map it's the red line train.
Check the legend and it will more than likely tell you.
depends on what the map represents, Latitude and Longitude for one, Isobars for another, may be contours, could be isotherms, could be isohyet, could be isopectic, could be isogon.
longitude or meridian.
A train it's a red line
Central meridian is a line on a map. It begins with the letter c.
a red line
A red line is used to show an open railway station. This answer is correct because if you were to check this your self using an os map, it would tell you the exact same
Conformal
A Red Line
A train it's a red line
its called an index or index conotour line and is every fitth line on a topographic map.
Central meridian is a line on a map. It begins with the letter c.
a red line
the cold front
A line on a weather map that connects places where the temperature is the same is called an isotherm.
borders
It is called the scale.
Redbridge on the Central Line - which is also coloured red on the tube map.
A red line is used to show an open railway station. This answer is correct because if you were to check this your self using an os map, it would tell you the exact same
Conformal