Since the middle Ages the sponge industry has been a profitable trade. Sponge harvesters are the first submarine walkers, seamen that special life surroundings brought together with the submarine world and marked their interests.
The sponge industry first developed on the Aegean Islands whose inhabitants are known as a very skillful hunters of the submarine. They were getting up to 30 meters down into the sea
with weight and later would surface freely. They used devices called tini under which they would breath caught air. They expanded the sponge industry on the rest of the Mediterranean.
Until the half of the 19th century the European market was supplied only with the Mediterranean sponge. Only around 1840 did one Frenchman discover a quality sponge in the submarine world of the Bahami Islands and in that way he established that sponge area.
The first note about the sponge hunt on the Croatian coast dates from 1522 and it mentions 2 men from Zlarin picking sponges for a sailsman from Šibenik who was selling them to Venice. That showed that the Adriatic sponge was of a good quality and that it could become a profitable work.
As presumed, the sponge trade developed then but it didn't have far- reaching effects nor did it leave visible traces.
Only the inhabitants of Krapanj were persistent in sponging and little by little they developed the trade. Today, they are known as the only sponge harvesters on the eastern coast of the Adriatic. In the late 17th century, Father Antun, who came from Crete, taught inhabitants of Krapanj how to pick and clean a sponge. At first, they were hunting from ships with fish spears and could reach the depth of 16 meters.
In the middle of the 19th century they had around 40 boats and in 1893 they introduced the first diving machine- soft space suit or heavy diving equipment. The Fishing Society from Trieste, supported by the Marine Government from Trieste, got that machine and gave it to an entrepreneur Josip Jurić. It promoted sponging into a very profitable economic branch.
The sponge cooperative which consisted of 16 divers, 6 diving machines and 30 boats was established by sponge harvesters from Krapanj in 1911. After World War I they received a financial help from the Marine Administration for sponge reconstruction, so in 1930 a small sponge treatment shop began to work on Krapanj.
In 1947, company «SPUŽVAR» was founded and within that company a big sponge refinary was established.
In 1956 «SPUŽVAR» from Krapanj, together with fish cooperatives from Zlarin, Žirje and Jezera, went with 30 divers and 14 boats to the coasts of Egypt and Libya to catch sponges.
Not only did sponge harvesters from Krapanj catch sponges but also, as excellent divers, they developed techniques for pulling out sunken ships and they participated in buildings and port and submarine instalation repairings.