Online Mapping Services - a comparison


Carillons, chimes and other tower bell instruments may be found in many places throughout the world.  Historically, the published descriptions of their locations have often been not very precise.  This has sometimes led to confusion not only about location but even about institutional identity.  Therefore, one of the author's aims in building up the site data portion of the GCNA Website has been to provide the best possible information about the location of each tower bell instrument.  Mapping services available on the Internet have afforded the opportunity to communicate information about site location in a graphical way that neatly complements verbal descriptions. 

However, the process of adding locator maps to site data pages, as well as that of constructing index maps of various types, has not been trouble free.  Changes in mapping services (see Map Service History) and differences in the features offered by the various services have imposed significant limitations on what information could be presented and how that could be done.  This page presents aspects of the various mapping services which the author has found to be significant in choosing which ones to use and in determining how to make the best use of their features.

Common features

Unless otherwise stated, all of the online mapping services described below offer(ed) the following features (though not necessarily together):

Online Mapping Services

The services are listed in the order in which they have been utilized or studied by the author.  Other mapping services exist on the Internet besides those listed here.  For each service, the advantages and disadvantages are listed in their order of significance to the author.


The MapBlast service, a component or subsidiary of, was used from the very beginning of the development of site data pages for the GCNA Website, starting in early 1997.  It is no longer available (see the Map Service History), and some of its valuable features have never appeared on any other mapping service.

MapBlast sample map, specified by latitude and longitude:  

MapBlast sample map, specified by street address:  


This mapping service was one of the components of, an online directory provider.  We began using it in mid-2001, after we first found the MapBlast service to be inoperable.  It is no longer available in its original form, though Switchboard offers an alternate service subcontracted from Microsoft.  (See Map Service History for details.)

MapsOnUs sample map, dynamic:   [ MapsOnUs Maps ]

MapsOnUs sample map, static:   [ MapsOnUs Maps ]

(The choice of which MapsOnUs icon to use for the two different types of map was ours.)

Yahoo! Maps

Yahoo maps are one of the component services of the well-known Internet company.  The inability to specify an icon location by latitude and longitude makes this service unsuitable for our purposes.

Yahoo sample map:   [ Yahoo! Maps ]


This mapping service is one of the component services of the MapQuest Internet company, which also offers driving directions, road trip planning, and yellow pages.  Originally, the inability to specify an icon location by latitude and longitude made this service unsuitable for my purposes.  However, it was and is possible to create a map dynamically from the MapQuest Website using lat/lon in either deg/min/sec or decimal degrees.  In 2005, I discovered that there is also a method (apparently not publicly documented) for specifying lat/lon in a link to MapQuest.  This was initially used to provide some locator maps for Canada, where the MapsOnUs service was not available; it is now being extended to the USA.
The ability to map outside the USA and Canada has not been tested.
MapQuest also offers an online World Atlas.

MapQuest sample map (by address):   [ MapQuest map ]

MultiMap (UK)

MultiMap appears to have originated as a UK mapping service, and as such it has particular applicability for sites in the United Kingdom.  (As of Feb.2006, it offered maps for all other European countries, plus a few elsewhere; none have been tested here.)

StreetMap (UK)

StreetMap is strictly a UK mapping service, and as such it has particular applicability for sites in the United Kingdom. 

Google Maps

This mapping service became useful when Google published an Application Programming Interface (API) specification for it in 2005; soon it was wildly popular with third-party developers.


As originally made available, Microsoft MapPoint did not offer any useful way to link from a Webpage to a map of a pre-specified location.  Recent changes in response to competition from Google Maps have resulted in a new service called Windows Live Local; this has not been tested for applicability to our purposes.

Once upon a time, the following information seemed relevant.  With the demise of MapBlast, it isn't; but it remains here as a historical curiosity.  (But see the Postscript below.)

NOTE: There appears to be a discrepancy between maps from MapsOnUs and those from MapBlast in terms of the latitude and longitude of observed features. It amounts to as much as 4 seconds of longitude (approximately 300 feet east-west at mid-latitudes) and as much as 1/2 second of latitude (approximately 75 feet north-south), depending on location. It is not yet known why this discrepancy occurs, nor how it varies, nor which maps are more accurate with respect to any official standards for geographical reference. The impact on our locator maps is as follows:

Postscript:   With the advent of Google Maps, I've found that some old locations which appeared visually correct at the time are not correct now.  This confirms that one of the former services was in error in its display of lat/lon values.

Disclaimer: Although the opinions stated above were developed by me during the course of my pro bono work as Co-Webmaster for the GCNA, those opinions are entirely my own and have not been endorsed by any other person nor by the GCNA.  They are presented here solely to illuminate some of the paths which I have attempted and chosen in the course of that work.

/signed/ Carl Scott Zimmerman

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This page was created 2002/03/08 and last revised 2006/03/17.

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