There's a new mapping resource available on Géoportail which I am particularly excited about. Using the website https://www.geoportail.gouv.fr/donnees/lidar-hd-mnt you can get access to lidar information. At the moment it's pretty basic as far as resolution is concerned, but it is still a good tool.
Lidar stands for Light Detection and Ranging, and is a remote sensing technology that uses lasers to measure distances to objects on the Earth's surface. It operates by emitting laser pulses and measuring the time it takes for the light to reflect back to the sensor. One of the advantages is that it can be set up to show ground forms underneath vegetation.
For instance, you may remember the following blog post, about being shown the ditches that surrounded a now disappeared chateau near le Grand Pressigny. https://daysontheclaise.blogspot.com/2019/04/walking-round-invisible-castle.html. See if you can spot it on the following image:
Aerial photos show nothing, but on the lidar it's obvious. If you can't see it, or want to make a closer inspection, it can be found here.
The other map fun I've been having is with Flightradar24. I was having a whizz around, seeing if there was any excitement. This caught my eye: on (or near) the border between Poland and Ukraine. Mapping? Drone patrol? Border patrol? Something nefarious? Have a guess.
I'll answer tomorrow.
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