sobota 8. července 2017

Franklin Expedition Interactive Web Map

At you can find an interactive map of places and routes associated with the Franklin Expedition. The controls should be intuitive, but it may be a good idea to add a few words about the content and functions of the map.

Map control

Control of the map

The above picture might be enough to understand the map control. The possibility to edit objects and add new ones will be discussed in the next article. Any questions, of course, are welcome.

Map content

Base and overlay layers

The base and overlay layers serve as a topographic map background. The difference between them is that the base map can be only one, whereas overlay maps can be turned on more.
The Arctic area is probably best mapped at the ESRI World Topo Map (e.g. concerning geographical names), the highest quality satellite map is probably HERE.

Topic layers

Thematic layers represent "Franklin" map content. The individual objects in these layers are described by several attributes (see below, the "Objects" section). When you click on the object, an information window for the object will pop up. The map contains the following "official" layers:
  • Franklin expedition
  • Previous expeditions (before 1845)
  • Rescue expeditions (after 1847)
  • Monuments and museums
Further, the map may contain different "working" layers, at present it is a layer
"Andrés (workplace)".
Layers are distinguished by colour when viewed on a map.


From a geometric point of view objects can be points, lines, and areas (polygons).
Each object must have a title and a category (see below). It can also contain a more detailed description, picture (photo) and max two related links.

Object categories

  • ship (floating)
  • wreck
  • sledge (land parties)
  • cairn
  • human remains
  • relics)
  • sighting (Inuit reports)
  • building
  • monument
  • museum 
  • geography (geographical names)

  • ship route
  • land route
In the case of points, object categories are distinguished by icons (by Gustav Vávra), in the case of lines by the line style (ship routes: full-line, land routes: dashed-line).
Icons in the order listed above (left to right and top to bottom). Author: Gustav Vávra
The last category of points – geography – is not displayed as an icon or other symbol - instead, the name of the object is displayed as a geographical name.

Technical background

For non-experts in IT: Do not worry if this section is a total mystery to you. It should not prevent you to use the map.
Technically, the map is powered by the OpenLayers javascript library, with free mapping services as the base and overlay layers (topographic and satellite maps).
The "Franklin" objects are retrieved in the GeoJSON format from the database. The output from the database in this format (used as a data source for the map) can be viewed at
Note: the map application is universal, most features and content sources are set up by configuration files, i.e. it can be used for any map content, not just for the Franklin's expedition. However, relevant documentation for such deployment is not ready yet.

Further plans

  • Object clustering. There is a lot of points in some places (e.g. London). It would be better to display only information about number of objects in such places (instead of objects itself) in small map scales.
  • Better display of geographical names (category "geography"). Name labels are currently hard.
  • Help for object categories (see list of icons above).

Questions? Comments and suggestions? Offer of cooperation?

Please, write to

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