About the Narberth History Map

How to use the map

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Map layers

Map Layers: to show/hide a layer. Move the slider towards the left to make a layer less opaque (more transparent), revealing the layer below it; useful for comparing two or more layers or a layer with the basemap. Click the i icon to see the title, author and publisher of the printed source of the layer.

Map markers

Location markers of Narberth places, grouped by themes, for example historical photograph locations, homes of Roll of Honor veterans. Click to open a popup with brief description and links to details.

Historical photo markers indicate the age, location and heading of an historical image marked on the map, from the photographer's point of view. Darker indicates older, lighter more recent images. Stand there today, face towards the arrow head, and compare.

Mark my location

Mark your current location, if your device has geolocation capabilities, and you give your permission. Tap/click the marker to open a popup where you can refresh your location or remove the marker; great resource for walks around town.

The cross-hair marker shows the location your device reports; the circle around it is its reported accuracy.

The Narberth History Movie

The Narberth history movie! Click the play button to animate a succession of history layers in your current map view. You can set the play rate, and pause and re-start the action. As it plays, you can continue to pan and zoom the map.

Find a Narberth address

Find a Narberth address by selecting a Narberth street, then entering a street number to drop a marker at the address; helps you keep track of your chosen location while you fade the layers in and out. Our database includes some historical addresses that no longer exist (usually the building has been razed).

address marker for an existing addressaddress marker for an address that no longer exists Click anywhere within the borough to see the nearest address, with a link to its profile on Narberth Addresses. The markers (L to R) indicate an existing and a defunct address.

Toggle the bottom layer (the basemap) between a map view and a satellite view. Default is map view.

Map settings

Check/uncheck the checkboxes to show/hide the map features.

Narberth borough boundary: Showing this is helpful for orientation when inspecting the pre-1895 map layers.

Extent of historical maps: This outline encompasses the area surrounding the borough that we plan to incorporate into every layer (see details below).

Map tile outlines: Each layer is comprised of a grid of 256 × 256-pixel images that fit together seamlessly, thus the term "tiles".

Historical map sources

The maps are from bound atlases of "Properties on the Main Line Pennsylvania Railroad From Overbrook to Paoli" published at four- to eight-year intervals. A. H. Mueller, who lived at 117 Forrest and was Narberth's first mayor, published four such editions from 1896 to 1920. His 1913 edition included a re-drawing of John Levering's 1851 map of Lower Merion which we use here, too.

All the maps from every edition (not just Narberth) are available in digital and physical formats:

Digital copies online

Physical atlases

Constructing the map

We started in 2014 with high resolution scans downloaded from the Lower Merion Township website in black and white (the atlases were printed in color). Since then, we are grateful to have obtained color scans from two sources, the Villanova University Digital Library (1877, 1913) and the Radnor Historical Society (1881, 1887, 1893, 1896, 1900, 1908, 1926), as noted in the map source info that accompanies each layer. This will allow us to replace those black and white scans with full coverage color ones.

After we obtain scans, we prepare them for the map:

  1. Image cleanup to remove scratches and speckles, clean edges, make colors consistent, touch up and composite cleaner versions of hard-to-read sections. This is the most time-consuming part of the process. Software: Adobe Photoshop
    Station circle, 1900 and retouching. "After" has 41% fewer bytes.
  2. Align image with GPS coordinates. We mark the same set of locations on the map image and a modern map grid. Prime candidates include street intersections which have not changed over the decades, and buildings still standing today. By correlating common points, the image can be rotated, skewed, stretched and locally warped to fit the modern map, a process called georeferencing but more graphically described as "rubbersheeting". Software: QGIS
    map with orthogonal grid before final georeferencing same map after georeferencing; the gird is warped and twisted showing the map tranformation
    The 1900 map and georeferencing.
  3. Slice the image into tiles. The map is comprised of 256×256 image tiles. Each zoom level requires its own set at appropriate enlargements. Software: MapTiler
  4. Tile image optimization to reduce file size for fast loading and consideration for your bandwidth and data limits. By using a two-step process, we have consistently been able to achieve 70% reductions in file size with no loss of quality. Software: Adobe Photoshop then FileOptimizer

The bottom layer, or basemap, is derived from OpenStreetMap, the Wikipedia of maps, which is to say that anybody can sign up for a free account and edit the map. Because we did just that, Narberth has building outlines and surrounding areas do not.

Whither the map?

History doesn't end at the borough border! So we want to start including Narberth's neighbors, just as you see on the pre-Narberth layers (before 1895). This means fitting together as many as seven pages from an atlas, not a trivial task given the different orientations and scales of each plate, and especially the unavoidable inconsistencies with the scanning process.

map with separate map plates outlined, and a square indicating the map area and plates being used
From Ellis Kiser and J. M. Lathrop, Atlas of Properties on Main Line Pennsylvania Railroad from Overbrook to Paoli (Philadelphia, A. H. Mueller, 1920), index page. Narberth is plate 5; the blue square represents the extent of the historical map area we plan to provide for each layer.

We want to show historic aerial and satellite photography on the map. In particular, the Delaware Valley Regional Planning Commission has made available aerial survey photographs at five year intervals starting 1959, and satellite imagery starting in 2000. There are other sources of photography dating back to the 1920s.

… and more layers, more photos, more markers! We think location is a great way to organize all sorts of information that pertains to an address, such as who lived there, when, what happened there, what it looked like, what's changed, what's stayed the same and more.

Technical requirements: Javascript must be enabled in your browser. Map functionality is tested in recent versions of Chrome, Firefox, Opera, Safari, mobile Safari, Edge and various browsers in Android 6+. Sorry, but we don't have the resources to test or adapt the Narberth History Map for Internet Explorer.

Cookies: The map uses cookies to remember the layers, opacity, zoom and map center you (or rather your computer or device) were viewing on your previous session in order to recreate them next time. The cookies are updated with every such change you make, but expire after 90 days if not refreshed. The map and satellite base layers, which are provided by third parties, may leave their own cookies. If you disable cookies, the map and website will still work.