In order to keep the map working at reasonable speed Google Maps needs
to limit the available features visible at once, quite simply the more
features shown the slower the map gets.

For MyMaps the features are split into pages, so that a reasonable
amount of data is shown on one page - effectively enough that will
work at a reasonable speed. This normally results in between 60-200
features at once, but sometimes that is not enough.

However Google Maps uses a different limited method when displaying
KML files; a regional geographical culling based method. A certain
number of features are shown, to give a reasonable overview, but then
as you zoom in more features become visible. This often results in
more results being visible, but importantly doesn't impose the
arbitrary pages, so its often more friendly on the user, as can just
zoom in on an area rather than flick though pages to find their area
of interest.

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the HowTo

And as MyMaps have an KML export, its quite easy to do. Unfortunately
the inbuilt KML export doesn't work with multiple pages, so :

* as you have multiple pages (as you reading this!) then I have a
little script to create a KML file that gets round the limitation:
....1. Goto http://www.nearby.org.uk/allMyMaps-to-kml.php
....2. Follow the instructions
....3. On the results page, right click the 'Download Google Earth KML
File' and copy the link to the clipboard

Now you have the URL of a KML file in the clipboard, simply return to
Google Maps, and paste in the URL in to the Search Box, and click
Search.

You should now see your MyMap content with the regional culling method
I mentioned :)

(Note: If you don't like the display of the nearby.org.uk domain in
the display, can simply download the KML file produced by the script
and host it on your own server, or googlepages.com for example)

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Going Further…

If want to 'share' it with others, just use the 'Link to this Page' to
get a shareable link

Note you can even save this 'display method' back to the MyMaps tab,
with the link on the left. Note you can even continue to edit the
source MyMap and after a few hours delay the changes will even show up
on the 'copy' - as the KML file is simply a 'geofeed' of the original
map (NetworkLink in KML parlance)

However if your map gains enough features that it splits onto an
additional page, when you will have to follow the above again, as the
KML has the number of pages hardcoded inside - I see no easy way round
this.

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