a recognizer configured to recognize a surrounding situation of a vehicle;

a driving controller configured to control one or both of steering and a speed of the vehicle on the basis of the surrounding situation recognized by the recognizer;

an acquirer configured to acquire first map information including lane information around a vehicle and reference information for identifying a position of the vehicle; and

an identifier configured to identify a traveling lane of the vehicle among one or more lanes included in a road on which the vehicle travels from the first map information on the basis of the reference information acquired by the acquirer,

wherein the driving controller causes the vehicle to travel by executing any one of a plurality of driving modes including at least a first driving mode in which a task of gripping an operator that receives a steering operation of the vehicle is not imposed on an occupant of the vehicle and a second driving mode in which a task imposed on the occupant is heavier than in the first driving mode and a task of gripping the operator is imposed on the occupant, executes the first driving mode when a traveling lane of the vehicle is identified by the identifier, switches from the first driving mode to the second driving mode when a first section in which a traveling lane of the vehicle is undefinable by the identifier and a second section having a fork having at least three branching lanes within a predetermined distance in the traveling direction of the vehicle, and changes lanes in the second driving mode to a lane in the first section in which the traveling lane of the vehicle is identifiable when the traveling lane of the vehicle is not identifiable and does so whether or not there is a lane increase in the first section.