The legal regime of transit passage through sea straits and maritime canals is of great importance for international relations. Straits are natural sea passages between two land parts, and maritime canals are man-made waterways. At the Third United Nations Conference on the Law of the Sea, one of the fundamental issues was the question of passing through sea straits which are used for international navigation. These include straits with a width of 24 nautical miles in which freedom of navigation applies, straits under the regime of innocent passage, straits under the regime of transit passage and straits under a special treaty regime. After the United Nations Convention on the Law of the Sea 1982 codified the navigational rights of states and introduced a new regime of transit passage, the regime of innocent passage remained in two categories of international straits. By establishing the transit passage institute, the maritime power states agreed to increase the maximum width of the territorial sea to 12 nautical miles, thus establishing a balance between the sovereign rights of coastal states and freedom of the sea, primarily freedom of navigation. The channels, which are of global interest for international maritime traffic, are internationalized by special contractual regulations in order to preserve the freedom of navigation for ships of all flags, without discrimination. The most important among them are the Suez Canal, the Panama Canal and the Kiel Canal. The international "Law of the Sea" was incorporated into the national law of the Republic of Croatia with the adoption of the Maritime Code in 1994. Ten years later, a new Maritime Code was adopted, which, with certain amendments, is still in force today.