.KML file extension

This is the basic program to work with .KML extension

Google Earth

Google Earth

Google Earth is a program that enables you to enjoy 3D views of the globe. You can explore cities, buildings and structures with the 3D buildings layer, see distant galaxies, view constellations, see 3D models of spacecraft and zoom into 360-degree photos from past space missions... (more)

The program works with the following extensions: kml, kmz and eta

.KML extension is also supported by the following programs:

Google Desktop

Google Desktop Google Earth KML

It's a desktop search application that provides full text search over your email.
Google Earth Pro

Google Earth Pro

Google Earth Pro is a shareware program for earth-mapping learners of all ages.
Google Desktop Search

Google Desktop Search Google Earth KML

Google Desktop Search, info when you want it, right on your desktop.

PoiEdit Keyhole Markup Languge

PoiEdit is a program for managing your POI (Places of Interest) files.
ArcGIS Explorer

ArcGIS Explorer

ArcGIS Explorer Desktop is a GIS viewer that gives you an easy way to explore.
Google デスクトップ

Google デスクトップ Google Earth KML

Google 桌面

Google 桌面 Google Earth KML

Poi Edit

Poi Edit Keyhole Markup Languge