1. Click on the map to select a location.
  2. Enter a date range. You can select a date range by year by dragging the handles of the slider or entering specific dates in the date fields.
  3. Adjust the scale at which you want to view results by dragging the guage in the scale ring. The closer to zero, the closer the zoom. You can manually change the value by clicking on the number.
  4. Click on a circle to get further information.

1500 2020