A drilling vessel the drilling vessel comprising: - a drilling tower having a firing line, along which a tubular string is passed into the sea during drilling activities, the firing line extending in a substantially vertical direction, and; - a tubular string support structure, characterized in that the support structure (3; 50) comprises: = two parallel rails (11; 51), which rails are provided on opposite sides of an elongated opening (12; 52; 112), wherein the firing line passes through said elongated opening between the rails (11; 111); and = two carts (13, 14; 53, 54; 113, 114), each cart having a hanger body (15; 115), which hanger body defines a vertical passage (16; 116) adapted to receive a tubular string supported in the firing line, and which hanger body (15; 115) defines a lateral passage (17; 117), in communication with said vertical passage (16; 116), allowing to place the tubular string in and remove the tubular string from said vertical passage, and wherein the carts (13, 14; 53, 54; 113, 114) are each supported by the parallel rails such that each cart can be moved between a central support position (18; 58), above the elongated opening (12; 52; 112) with the firing line passing through the vertical passage (16; 116), and a secondary position above the elongated opening with the firing line passing outside the vertical passage (16; 116), and wherein, when both carts (13, 14; 53, 54; 113, 114) are located in their secondary position, the carts are located on opposite sides of the firing line, such that between the carts (13, 14; 53, 54; 113, 114) there is a passage for passing through large objects along the firing line. - a drilling tower having a firing line, along which a tubular string is passed into the sea during drilling activities, the firing line extending in a substantially vertical direction, and; - a tubular string support structure, characterized in that the support structure (3; 50) comprises: = two parallel rails (11; 51), which rails are provided on opposite sides of an elongated opening (12; 52; 112), wherein the firing line passes through said elongated opening between the rails (11; 111); and = two carts (13, 14; 53, 54; 113, 114), each cart having a hanger body (15; 115), which hanger body defines a vertical passage (16; 116) adapted to receive a tubular string supported in the firing line, and which hanger body (15; 115) defines a lateral passage (17; 117), in communication with said vertical passage (16; 116), allowing to place the tubular string in and remove the tubular string from said vertical passage, and wherein the carts (13, 14; 53, 54; 113, 114) are each supported by the parallel rails such that each cart can be moved between a central support position (18; 58), above the elongated opening (12; 52; 112) with the firing line passing through the vertical passage (16; 116), and a secondary position above the elongated opening with the firing line passing outside the vertical passage (16; 116), and = two parallel rails (11; 51), which rails are provided on opposite sides of an elongated opening (12; 52; 112), wherein the firing line passes through said elongated opening between the rails (11; 111); and = two carts (13, 14; 53, 54; 113, 114), each cart having a hanger body (15; 115), which hanger body defines a vertical passage (16; 116) adapted to receive a tubular string supported in the firing line, and which hanger body (15; 115) defines a lateral passage (17; 117), in communication with said vertical passage (16; 116), allowing to place the tubular string in and remove the tubular string from said vertical passage, and wherein the carts (13, 14; 53, 54; 113, 114) are each supported by the parallel rails such that each cart can be moved between a central support position (18; 58), above the elongated opening (12; 52; 112) with the firing line passing through the vertical passage (16; 116), and a secondary position above the elongated opening with the firing line passing outside the vertical passage (16; 116), and