do the map symbols mean?
displays map features using cartographic symbols typically
using different colors to represent different values
for a feature attribute. For example, the color of symbols
used to display barriers represent the type of blockage;
total, partial, non-barrier structure,
or unknown. You can see a legend for the currently displayed
layers by clicking on the ‘Legend’ button
on the upper left of the display.
the legend is visible, you can display the layer list
by clicking on the ‘Layers’ button.