Luja

As starting point I recommend the railway station in Puchberg/Schneeberg (parking space is available if you arrive in time). The best way to visit the cache is to do a round-trip visiting the summit of Himberg. I didn't find any information about the hut (it was closed when we were there), so you'd better bring your own provisions. There are two paths leading from Puchberg up to the summit. The western path offers several nice viewpoints (most of them with benches, such as the Geierwand) and more sun than the eastern trail.
The path via the cave seemed to be steeper and marked less well to us. The terrain-rating accounts for snow, under summerly conditions it might seem exaggerated.

The cave (Allelujahöhle) is situated at about 750 m a.s.l., it can't be missed as the marked path makes a turn there (culture trail). According to legend local people sought shelter there during the Ottoman wars (I found 1532 in a book, according to other documents around 1680), until someone made a fire in the cave. So the refugees were found and killed. Several human skeletons were found in the cave.
The cave is almost 13 m long, but it has no dark parts and no further extensions (which makes it uninteresting for bats). A torch is not necessary here, from the portal the whole cave can be overlooked.
In order to fetch the cache it is not necessary to enter the cave, the cache is hidden outside!
In winter watch out for ice falling down from the portal's ceiling. If it is cold enough the ground is covered by small icy stalagmites (mind your step and don't destroy them!).

The unbelievable coordinates were actually measured next to the cache. The eastern values were very stable, the northern values varied a bit.
The cache is a very small Lock-Lock-Box. Initially it contained a logbook, two ducks and a hedgehog. Please bring your own pen! Near the cache watch out for shards of broken glass.

Have Fun!