Here's a nice pic:
Its from http://surfacetemperatures.blogspot.co.uk/2014/06/global-land-surface-databank-version.html (but I cut it a bit to make it prettier). The colour bar is number of years.
Refs
* Understanding the effects of changes in the temperature scale standards through time
Isn't the greater Alpine region pretty? Lots of black dots with more than 200 years of data. They put a lot of effort in data rescue.
Ya victor,
it looks like they have about 2K stations that we dont have..
Should be fun to use them as out of sample test