Wellbore drilling system comprising: - a drilling tower, - a drill floor having a well center through which a drill string passes along a firing line, - a drilling tubulars rotary storage rack (10, 11) adapted to store multiple drilling tubulars in vertical orientation, preferably multi-jointed tubulars, said drilling tubulars rotary storage rack being rotatable about a vertical axis and having storage slots for storage of multiple tubulars in vertical orientation, the drilling tubulars rotary storage rack including a drive (18, 19) to rotate the drilling tubulars storage rack about its vertical axis, said drilling tubulars rotary storage rack comprising a central vertical post (10a, 11a) and multiple discs (15a, 15b, 15c) at different heights on the post, at least one disc being a fingerboard disc having tubulars storage slots, each slot having an opening at an outer circumference of the fingerboard disc allowing to introduce and remove a tubular from the storage slot, - a tubular racking device (40, 40') having at least a lower first tubular racker assembly (41, 41'; 141, 141') and at least a second tubular racker assembly (42, 42'; 142, 142') operable at a greater height than the first tubular racker assembly, each tubular racker assembly comprises a base (41b'; 141b'), a motion arm (41b; 142'b) connected to said base, and a tubular gripper member (41t; 141t) connected or connectable to the motion arm and adapted to grip a tubular, wherein the tubular racking device is adapted to grip and retain a drilling tubular by the tubular racker assemblies, and wherein the tubular racking device is adapted to place a tubular in and remove a tubular from the drilling tubulars rotary storage rack, and wherein the tubular racking device has a reach at least allowing to transfer a tubular gripped by said first and second tubular racker assemblies between the drilling tubulars rotary storage rack and a position of the tubular aligned with the firing line above the well center so as to allow for building and disassembly of a tubulars string, characterized in that the at least one fingerboard disc is composed of multiple fingerboard disc members (115a - 115j) that are releasably connected to the central post. - a drilling tower, - a drill floor having a well center through which a drill string passes along a firing line, - a drilling tubulars rotary storage rack (10, 11) adapted to store multiple drilling tubulars in vertical orientation, preferably multi-jointed tubulars, said drilling tubulars rotary storage rack being rotatable about a vertical axis and having storage slots for storage of multiple tubulars in vertical orientation, the drilling tubulars rotary storage rack including a drive (18, 19) to rotate the drilling tubulars storage rack about its vertical axis, said drilling tubulars rotary storage rack comprising a central vertical post (10a, 11a) and multiple discs (15a, 15b, 15c) at different heights on the post, at least one disc being a fingerboard disc having tubulars storage slots, each slot having an opening at an outer circumference of the fingerboard disc allowing to introduce and remove a tubular from the storage slot, - a tubular racking device (40, 40') having at least a lower first tubular racker assembly (41, 41'; 141, 141') and at least a second tubular racker assembly (42, 42'; 142, 142') operable at a greater height than the first tubular racker assembly, each tubular racker assembly comprises a base (41b'; 141b'), a motion arm (41b; 142'b) connected to said base, and a tubular gripper member (41t; 141t) connected or connectable to the motion arm and adapted to grip a tubular, wherein the tubular racking device is adapted to grip and retain a drilling tubular by the tubular racker assemblies, and wherein the tubular racking device is adapted to place a tubular in and remove a tubular from the drilling tubulars rotary storage rack, and wherein the tubular racking device has a reach at least allowing to transfer a tubular gripped by said first and second tubular racker assemblies between the drilling tubulars rotary storage rack and a position of the tubular aligned with the firing line above the well center so as to allow for building and disassembly of a tubulars string, characterized in that the at least one fingerboard disc is composed of multiple fingerboard disc members (115a - 115j) that are releasably connected to the central post.