www.speleophilately.com
 

Križna jama (Cave of the Cross) is over 8 km long cave with un underground stream situated in the karst land between the poljes of Lož and Cerknica; the entrance altitude on 630 m above s.l. It is considered as "the most beautiful" Slovene cave.

The name of the cave is after "Križna gora (= Cross Mountain)", that is the hill above the cave entrance with the church of the Holy Cross on the top of it.
Stalagmite "Križ (=Cross)" from Križna jama (= cave)

The cave is known long time ago, it is first mentioned in literature in 1832 (Shaw 1979). Already in that time it was the aim of some curious tourists and a sort of guide was at the entrance. At the end of the last century it became known because of numerous cave-bear (Ursus spelaeus) bones excavated in the lateral "Bear Gallery".

But up to 1929 only the entrance part, dry one, of the cave bas been known. The continuation was impossible for the reason of the "Lake" - cave river extending from one cave wall to the another.

In the year 1929 the members of DZRJ (Društvo za raziskovanje jam = Society for Caves Exploration), founded in 1910 in Ljubljana, succeeded to penetrate further upstream and thus they discovered the inner parts of the cave. They began to survey the new discovered parts in 1930 under the guidance of I. Michler and A. Šerko (Michler 1934). In the same year I. Michler, J. Kos and T. Krašovec came up to so called "Matjaž gallery" (Bohinec 1963).

In 1931 I. Michler, J. Kos and Franci Bar reached further from "Križna gora" and "Matjažev rov" so called "Kristalna dvorana (=Crystall Hall)", about 3 km from the entrance. The hall is 75 m high, huge pile of richly decorated fall down blocks and stones in it is named "Kristalna gora (=Crystall Mountain)".

One of the biggest stalagmites on the Kristalna gora is in the form of cross and is named "The Cross (Križ in Slovene language)". And this Cross is the stalagmite depicted on the stamp from 1945 "Ljubljanska pokrajina- Provinz Laibach", later used for the new state of Yugoslavia with an overprint (issued 7.6.1945).

F. Bar. who was as we can say.official photographer of DZRJ between the 1st and 2nd World War, made the photos (on the glass plates) of the inner parts of the cave in the years 1934-35. He has made some shots of the stalagmite "Križ" too. One of his photos of "Križ" is also published in a well known guidebook "Postojnska jama and the other curiosities of Karst" (Šerko & Michler 1952)

After 1935 it was also some excursions to Križna jama. but this activities ended with the beginning of the 2nd War (1941). In any case the photo of "Kriz" depicted on the stamp was taken in the period 1934-1940.

Bibliography:

Bohinec, V., 1963: Die Križna jama (Kreuzberghöhle) bei Lož, Slowenien.
3rd International Congress of Speleology, B. II, 211-214, Wien
Michler, I., 1934: Nova odkritja v Križni jami. Proteus 1/9, 188-195, Ljubljana
Shaw, T.R.. 1979: Križna jama, the earliest (?) published account.
Naše jama, 20, 59-62. Ljubljana
Šerko, A. & I. Michler, 1952: Postojnska jama. in druge zanimivosti krasa.
1-166, Ljubljana