At what minimum height above terrain does a vertical structure need to be indicated on a sectional map?
Refer to Aeronautical Chart Users Guide 2017. There are 351,148 obstacles in the database. Generally it is when ”a manmade obstacle is 200' above the highest terrain in the quadrant”. However, “in high density areas like city complexes, only the highest obstacle is represented on the chart”. Then they do the calculations below to show the obstacle on the chart.