Abstract: A ship including a plurality of engines and a plurality of exhaust gas purifiers provided on respective exhaust paths for exhaust gas from the engines. Each exhaust gas purifier includes a casing and an opening. The casing accommodates a purification catalyst for purifying the exhaust gas. The opening serves to place the purification catalyst into or displace the purification catalyst from the casing. The exhaust gas purifiers are arranged so that the respective openings of the exhaust gas purifiers face an identical space and operation directions of an operation performed through the openings in at least two of the exhaust gas purifiers cross.