The POSEIDON was built in 1976 and belongs to the pool of mid-size German research vessels. Its home port is in Kiel, Germany, and it is owned by the state of Schleswig-Holstein. The ship, which was named after the ancient Greek god of the seas, is deployed mainly in the Northern Atlantic and the Mediterranean. The POSEIDON is easy to navigate and retains a stable position even in heavy seas. In the early 1980s, the vessel was upgraded for expeditions to explore the deep sea. On POSEIDON the focus of research is on oceanography, marine biology and geology. For these research activities, the POSEIDON is equipped with five laboratories, winches, cranes and echo sounders. Some pieces of mobile equipment, such as a multi-beam echo sounder and a water sampling rosette, can also be used with other vessels. Furthermore, the POSEIDON is well-suited for the deployment of the submersible JAGO.The ship is available all year round, considering all applicants and institutional obligations. The range of operation covers the North Atlantic, the Baltic Sea, the Mediterranean Sea and the Black Sea.The period of cruise planning and lead time for application is one year, with a deadline of 30 September of the preceding year.The allocation of ship time, quality control and eligibility are under the responsibility of the steering group on the operation of medium-sized research vessels, based on a successful scientific evaluation.The current cost for the ship per diem at sea is €11,500.Cruising speed, range: 9 kn, 5000 nm. Endurance at sea: 24 days.