Recreational craft

A recreational craft is a water craft with a total length of 2.5-24 metres (e.g. a boat, a sailing yacht, a motorboat, etc.), used for recreation, regardless of the registration. Water crafts used for competitive sports and training and marked accordingly by the sports association (e.g. a jet, a windsurfing board, a sports sailing yacht, a sports sailboat, etc.) and water crafts with a primitive structure (e.g. a dugout, a dory, small flat-bottomed boat, a narrow boat, a canoe, etc.) and water crafts with a special structure are not considered to be recreational crafts.
A ship with a total length below 12 metres is a water craft used for economic activities, professional work, state administrative purposes or vocational training.
A jet is a water turbine vehicle without a cockpit and with a stationary engine, with a total length of up to 4 m, driven while sitting, standing on knees or standing up.

ARK website also provides information about registering a recreational craft and about inspection of a recreational craft before registration.