According to the customary law, upon entering the waters of a foreign country, next to the flag of origin, the flag of the foreign country that the ship intends to enter is also flown. None of the crew is allowed to leave the ship or boat at first, and the border guards go to the ship and after checking all the personnel documents and documents related to the ship, including the bill of lading and itinerary, issue the shipping visa to the crew. In some cases, pleasure boats can go to the border guard centers on the coast in person and request a visa to enter the country or pass through the waters of that country.