Vessel (200, 300, 400, 600) comprising: a cargo transloading system, said cargo transloading system comprising: a crane (210, 310, 410, 610) supporting a cargo handling device (318, 418), and a counterweight arrangement (450, 550), said cargo handling device (318, 418) being rotatable about a vertical axis of rotation arranged with a first fixed offset in a first side direction with regard to a first vertical plane coinciding with a longitudinal centre axis of said vessel (200, 300, 400, 600), said counterweight arrangement (450, 550) comprising a weight (452, 552, 652) characterized in that said weight (452, 552, 652) is movable such that the mass centre of said weight (452, 552, 652) is laterally displaceable between a first end position (556, 656) in which said mass centre is arranged in the vicinity of said first vertical plane and a second end position (558, 658) in which said mass centre is arranged with a second offset in a second side direction opposite to said first side direction with regard to said first vertical plane, said counterweight arrangement (450, 550) being arranged to move said weight (452, 552, 652) while said cargo handling device (318, 418) is rotated about said axis of rotation as a function of the rotation angle (α). a cargo transloading system, said cargo transloading system comprising: a crane (210, 310, 410, 610) supporting a cargo handling device (318, 418), and a counterweight arrangement (450, 550), said cargo handling device (318, 418) being rotatable about a vertical axis of rotation arranged with a first fixed offset in a first side direction with regard to a first vertical plane coinciding with a longitudinal centre axis of said vessel (200, 300, 400, 600), said counterweight arrangement (450, 550) comprising a weight (452, 552, 652) characterized in that said weight (452, 552, 652) is movable such that the mass centre of said weight (452, 552, 652) is laterally displaceable between a first end position (556, 656) in which said mass centre is arranged in the vicinity of said first vertical plane and a second end position (558, 658) in which said mass centre is arranged with a second offset in a second side direction opposite to said first side direction with regard to said first vertical plane, said counterweight arrangement (450, 550) being arranged to move said weight (452, 552, 652) while said cargo handling device (318, 418) is rotated about said axis of rotation as a function of the rotation angle (α). a crane (210, 310, 410, 610) supporting a cargo handling device (318, 418), and a counterweight arrangement (450, 550), said cargo handling device (318, 418) being rotatable about a vertical axis of rotation arranged with a first fixed offset in a first side direction with regard to a first vertical plane coinciding with a longitudinal centre axis of said vessel (200, 300, 400, 600), said counterweight arrangement (450, 550) comprising a weight (452, 552, 652) characterized in that said weight (452, 552, 652) is movable such that the mass centre of said weight (452, 552, 652) is laterally displaceable between a first end position (556, 656) in which said mass centre is arranged in the vicinity of said first vertical plane and a second end position (558, 658) in which said mass centre is arranged with a second offset in a second side direction opposite to said first side direction with regard to said first vertical plane, said counterweight arrangement (450, 550) being arranged to move said weight (452, 552, 652) while said cargo handling device (318, 418) is rotated about said axis of rotation as a function of the rotation angle (α). said cargo handling device (318, 418) being rotatable about a vertical axis of rotation arranged with a first fixed offset in a first side direction with regard to a first vertical plane coinciding with a longitudinal centre axis of said vessel (200, 300, 400, 600), said counterweight arrangement (450, 550) comprising a weight (452, 552, 652) characterized in that said weight (452, 552, 652) is movable such that the mass centre of said weight (452, 552, 652) is laterally displaceable between a first end position (556, 656) in which said mass centre is arranged in the vicinity of said first vertical plane and a second end position (558, 658) in which said mass centre is arranged with a second offset in a second side direction opposite to said first side direction with regard to said first vertical plane, said counterweight arrangement (450, 550) being arranged to move said weight (452, 552, 652) while said cargo handling device (318, 418) is rotated about said axis of rotation as a function of the rotation angle (α).