I bet it means channel
Switzerland
Rivers
It usually stands for rivers or borders, depends which map you're looking at.
A map or diagram starts with ch is a chart.
"Ch" on an Ordnance Survey map typically stands for "church." It marks the location of a church or a place of worship on the map.
Church
Ch can stand for channel as in television channel.
The major rivers in Russia as shown on the map are the Volga, Lena, Yenisei, and Ob rivers.
A Topographic map
A map drawn or printed on paper is a physical map.
CH is the international badge for Switzerland, or Helvetia.
Rivers belong in the physical realm, but may also be shown on a political map.