Glagolitic script appears in two shapes, as: round or Bulgarian and angular or Croatian. Glagolitic script is most probably an original work by Constantine the Philosopher, created in the 9th century, who was using Glagolitic script to translate church books into Old Slavic language.
In the memory of the Glagolitic alphabet and all Glagolits throughout Croatian history, the Baška Glagolitic path on the island of Krk was composed of sculptures in the shape of Glagolitic letters. It starts with the sculpture in the shape of the Glagolitic letter "Az" Treskavac, and ends with the last sculpture on the waterfront in Baška harbour. The letter sculptures are placed on prominent positions along the valley and the surrounding slopes. Each letter signs one of Croatian towns, and they are made of indigenous Krk limestone "sivac".
The purpose of the path is to instruct the visitors of the Baška area by interactive methods and permanently guide them through the historic and cultural significance of this area.
Glagolitic letter I is located in the town of Baška on the island of Krk where you will find your treaure.
Stone upon stone would be a good hint but in the usual Croatian sense.