I had a look at this property which was recently for sale. It is by the Herenthage, on the same ridge as the Tower Hamlets redoubts.
The house itself was a wreck, probably not properly inhabited since the 1950s, no running water, no washing facilities, no obvious kitchen and only an outside privvy.
The chicken house at the back of the property is made of broken up bunker, there are light railway rails being used as fence posts, and left of the main yard under years growths of undergrowth, there is a large ground level concrete structure which is pretty clearly the top of a subterranean bunkers.

The 'For Sale' page can still be seen here, with photos:-

http://www.era.be/nl/aanbod/panddetail.aspx?objectid=148230

The bunker can just be seen in the middle of the left hand photo in the second row of photos

Unfortunately, I'm sure the new owners will probably redevelop the site.

My question is, is there any protection in Belgian law for bunker structures on private land? Can someone get in there and excavate this probably untouched since the war structure?

I actually wanted to buy this property, but the proportion of the money being asked for "a la Belge" was disgraceful. You Belgians will know what I mean!

Hugh

Wit a few exceptions, such as the Zandvoorde command bunker or the Zigeler bunker I do not know of any protected bunkers in the area. An inventory was made last year, but this one was not complete and only for the 'Westhoek'. Many unique bunkers have been destroyed ieven in the last few months, especially in the coastal area.
As usual in belgian politics much blabla but no action at all is taken...