It is unclarified if the name "Hopfenbach" ("bach" = "creek") is derived from the hop plantations in this area or from the verb "to hop".

The latter would point to a peculiarity which you can see on the meadow in front of you if you are at the listing coordinates.

The creek, which rises south-east of Bachl, leaves the forest at the southern side of the clearing. But usually you won't find any outlet on this meadow - the creek vanishes into the subsoil. The exact place changes constantly. Sometimes the water seeps away unspectaculary, sometimes it falls roaring into a deep sinkhole. In case there is a lot of water, even a small pond can develop. Only if there is a very huge amount of water, it continues its way through the - normally dry - Hopfenbach valley.

The reason for this phenomenon are alternating layers of lime and marl, which can be hundreds of meters thick. Throughout millions of years, the lime weathered. Subterranean cavities and water-bearing crevices came into being, throughout which the Hopfenbach continues ist way from here.

Areas with such geological structures are called karst. Above ground, you can often see dolines as they are called - craters, formed by erosion processes of different kind.

In order to being allowed to log this cache, you must fulfill the following requirements:

- Take a picture of the meadow on which the Hopfenbach vanishes. If the condition of the ground allows it, the point of seeping-away should be visible on the picture as clear as possible. This is to document the changes at this location.

- Take a picture of you and / or your GPS receiver in front of the information board (voluntarily).

Please add both pictures to your log entry. In your log entry, please also describe how the point of seeping-away and the meadow did look when you were there.

Answer the following questions:

a) How many million years ago the rock layers mentioned above formed ?

b) In which country / area the karst phenomenon was desribed for the first time ?

c) A picture on the board shows a deep hole into which the creek poured on a special day. Look on the date. What happened on this day ?

d) Which unusual plant is growing on the meadow where the Hopfenbach vanishes ?

e) What ist the origin of the holes, in which the creek vanishes, according to a local legend ?

f) What can you see close to the information board (you must answer this backup question only in case the board is completely destroyed or removed or if your German is not good enough to understand the text on the board) ?

- wayside cross
- statue of the Virgin Mary
- wooden mushroom
- information board about forest birds

Send the answers to those questions to me. If you are sure that your answers are right, you don't need to wait for my log permission. But in case I do not receive the right answers, I will delete the log entry.

I did'nt see a prohibition sign, but I recommend you to park your car at N 48° 49.709 E 011° 56.111 at the edge of the forest. From there to the cache location, you have to walk about 1.7 kilometers on useable forest trails. The trails are suitable for strollers if they are somewhat cross-country qualified.

Close to the parking location, there is a bus stop of the VLK bus line 6 (the name of the bus stop is "Großmuß Abzw.").