See instructions below.          Select map to overlay       

   Instructions (based on Google Maps implementation as of Jan 2017) -

     Be patient!  Loading and adjusting the display may be slow because of the amount of data.

     If you are not familiar with Google Maps, use the following steps.
     - In the upper left corner, select the map display you find best for locating an area of interest.
        (Map displays a road map, while Satellite displays overhead photography with current buildings shown.)
     - Adjust the zoom level using the + or - buttons in the bottom right corner.
         If you have a scroll wheel on your mouse, that may also be used to adjust the zoom.
     - To move the map, hold down the (left) mouse button in the window and drag it in any direction.

     The 1886 Sanborn map overlay is loaded when the window is first opened and is centered on City Hall.
     Maps are initially displayed in the satellite mode with labels disabled to reduce clutter.
     Labels can be turned on by checking the 'Labels' box under the 'Satellite' button in the upper left of the map.
     A pull-down selection box is provided above the map window to select the desired overlay.
     A slider is included in the upper right corner to adjust the overlay transparency.
     Moving the slider all the way to the left turns the overlay off.

     If you don't see an overlay after moving the map, the display may be outside the limits of the selected overlay,
     or the zoom level may be too high or too low.  (Overlays are disabled at both high and low zoom levels.)
     To center the map back on the immediate area of Concordia, click the 'Center' box at the top right of the map.
     (This is always a good way to return to the default map display, like when the map changes to a world view.)

     To enter Google StreetView, simply drag the little yellow figure standing above the + and - buttons to the area on the map where
     you want StreetView to start.  (This must be an area that was photographed by Google.  You will see roads that were photographed
     highlighted in blue.)  
     To get back to the earlier overlay display, click on the left arrow in the upper left corner of StreetView.  

     To return to any other part of the website, either click on 'Return to home page' at the top or close the current tab in your browser
     where you can restart the overlay display from the previous window or switch to any other page.

   Notes:

     The maps were obtained from the Library of Congress Digital Collections.
     Inserts in some sheets were extracted and displayed separately.
     While the alignment of the overlay maps isn't perfect, it is reasonably close;
        so you should be able to determine where old buildings were.
     These overlays use old names for the streets of Concordia, namely:
	Schiller = Main Street		Henry = 6th Street
	Garfield = 2nd Street		Caroline = 7th Street
	Lincoln = 3rd Street		Boggs = 8th Street
	Conrad = 4th Street		Berlin = 9th Street
	Ambrose = 5th Street		Hamburg = 10th Street