( previous post: 2016-09 Bundeswehr garrisons)
Let's have a second look at garrisoning, and how it should be done on a blank sheet of paper - which is approx. the way it should be done with the long term in mind:
Important training areas (open fields, woodland, hilly terrain and for light infantry also swamps and mountains) that do not need to be erected should be close. In Germany this means that army manoeuvre brigades should probably be sited in Saxony and Saxony-Anhalt.
Specialised infrastructure is an important determinant as well. A well-sized combat training village cannot be raised next to all barracks for financial reasons. You either cluster the barracks whose troops need to train in such areas close to them or they will end up with too few training sessions there.
This leads to huge economies of scale benefits with clustering brigades together, with them sharing training areas.
Another benefit of such a layout would be that these brigades could frequently engage in scripted and free play exercises against each other or 2/3 of one against the other plus 1/3 of its own for a 1:2 inferiority in the defence and so on. It's no wonder that such exercises are rare when you site your brigade barracks hundreds of km apart.*
Then there are reserves. An army that's not meant to please itself in peacetime (but to deter and if need be fight for a quick status quo ante conflict ending) needs reserves, including entire reserve army manoeuvre formations.
This leads to a very promising scheme:
Two brigades are based together no more than 50 km apart with most or all important training areas within 100 km radius. Two inactive 'shadow' brigades are their sibling brigades, sharing the very same barracks and vehicle parks. The reserves' equipment would be kept in good order and modern, for the active brigade would take the reserves' vehicles (99-100% ready to go, regardless of recent exercises) in the event of crisis and deploy quickly. The reserve personnel would be called up, take the vehicles that the active brigade was using for training (typically 80-95% ready to go), repair them, execute a series of exercises to get ready, repair again and then deploy using the tank transporters that already helped the first wave to deploy.
This way one could even have up to four brigades in one region, using two brigade-sized barracks, one 'urban' combat training area, some training areas with woodland, woodland on hills and open fields.
An army of the German Heer's size would need no more than four such clusters, and they should probably be in Saxony-Anhalt and Saxony.
Now obviously, despite the efficiency in operations and layout, this would still cost billions of Euros for new barracks and training areas. We have less than two brigades worth of forces in those places so far. To pull off something like such a garrisons reform would require to convince the parliament to spend several billions not on extra troops or equipment - things that easily communicate extra combat power - but on better conditions for training and living. The army would even need to close several actually fine barracks that just happen to be in quite pointless areas.
This was meant for typical army brigades. A militia force would no doubt need barracks (or rather equipment pools) close to where the militiamen live, thus many close to population centres and few in very rural regions.
Army corps support units (that tend to have very road march-capable wheeled vehicles only) may also be dispersed, ideally between two or three clusters so they can join the brigade-level exercises with little effort.
*: I preferred to not talk much about the nonsense of dispersing one brigade into multiple towns..