2008 AD., Germany, Federal Republic, 100th Anniversary of the German Youth Hostel Association commemorative, Karlsruhe mint, 10 Euro, KM 283.

Germany, Federal Republic, 100th Anniversary of the German Youth Hostel Association commemorative, engraver: Hans Joa Dobler, Karlsruhe mint, 2009 AD., issued 13/08/2009 AD.,
10 Euro (ø 32,5 mm / 18,00 g), 0.925 silver, 18,00 g theor. mint weight, mintage 1.810.000 (in total), axes medal alignment ↑↑, plain, immerged lettered edge,
Obv.: BUNDESREPUBLIK - DEUTSCHLAND 2009 / G 10 EURO , issuer, date, mint mark "G" and value in a triagle (hostel roof shape) around German national emblem eagle, 12 stars of Europe in fields around.
Rev.: 100 JAHRE - JUGENDHERBERGEN / 1909 - 2009 , Alterna castle from the logo of Jugendherbergswerk, commemorative inscription "100 YEARS OF YOUTHHOSTEL" in the form of a triangle around, small roofs/triangles above, dates below.
Edge: plain with immerged inscription "BEGEGNUNG GEMEINSCHAFT TOLERANZ . " .
KM 283 .

Year / Mint Mark / Mintage
2009 / G / 1.610.000
2009 / G / 200.000

The German Youth Hostel Association (German: Deutsches Jugendherbergswerk) or DJH, founded at Altena Castle in North Rhine-Westphalia, is a not-for-profit, registered association (eingetragener Verein). Through the state (Bundesland) associations it is the representative of the 536 youth hostels in Germany (as at 2013) and thus the largest member of the international youth association, Hostelling International (HI). The headquarters has its seat in Detmold and is divided into 14 state associations and 218 local and county volunteer associations. It has more than 2 million members.

Altena Castle (German: Burg Altena) is a Medieval hill castle in the town of Altena in North Rhine-Westphalia. Built on a spur of Klusenberg hill, the castle lies near the Lenne in the Märkischer Kreis.
The castle was erected by the early Counts of Berg in the early 12th century. Eventually, the House of Berg abandoned Altena and moved their residence to Hamm.
Supposedly, the castle was built by the brothers Adolf and Everhard von Berg around the year 1108 after Henry V granted them land in Sauerland. On Wulfseck Mountain they built their castle, which they named Wulfeshagen, later Altena. This is one of the three legends of the establishment of the county of Altena and the building of the castle.
After the acquisition of Mark near the city of Hamm in 1198, the counts of Altena took Mark Castle as their primary residence and called themselves the Counts of the Mark. They occasionally inhabited Altena Castle and from 1392 onward it was used as a residence for the county bailiff (Amtmann).
In 1912, Richard Schirrmann established the world's first youth hostel within the castle, which is still in use today (Jugendherberge Burg Altena).

more on https://en.wikipedia.org/wiki/German_Youth_Hostel_Association , https://en.wikipedia.org/wiki/Altena_Castle