Cargo ships were loaded in Kalkan's harbour to sail for the far reaches of the Ottoman Empire carrying charcoal, silk, olive oil (still produced in Kalkan) and wine, as well as cotton, grain, sesame seed, flour, grapes, acorns used for dye, and lumber from the vast cedar and pine forests.
By the early 20th century Kalkan had become quite a sizeable village. At the turn of the century it had its own custom’s house and in 1915 there were reportedly seventeen restaurants, a goldsmith, a shoemaker and several tailors. The first local elections were held in 1928 and in 1937 the present elementary school was opened. Following World War I, the exchange in population between the new Turkish Republic and Greece took place in 1921 during the Turkish War of Independence. Most of the Greek origin people then living in Kalkan left Turkey (some going to the nearby Greek island of Meis), but trading continued until it faded away in the 1950’s due to the improvement of the Turkish road system and the adoption of overland transport. With no more sea trade, the population of Kalkan trickled away as people moved to larger coastal cities to find work.