A transport apparatus for transporting a carriage base, comprising: a body; a fork having a shape extending from the body, the fork having one portion supported by the body and another portion protruded from the body, the fork is insertable into the carriage base and extractable from the carriage base, the fork being configured to be inserted into the carriage base when transporting the carriage base using the transport apparatus; a lifting unit including one or more links; a control unit configured to control at least the lifting unit; a primary rotatable member mounted at a front end portion of the fork via the lifting unit, such that a relative position of the primary rotatable member with respect to the fork is changeable using the lifting unit, having a contact point at the point on the circumference of the primary rotatable member where it contacts the floor or step member; an auxiliary rotatable member (4, 5), having a contact point at the point on the circumference of the auxiliary rotatable member where it contacts the floor or step member, mounted such that the contact point of the auxiliary rotatable member (4, 5) is settable at a position lower than the contact point of the primary rotatable member when the fork is lowered using the lifting unit, the auxiliary rotatable member being mounted either at a front rotatable-member-attaching position of the fork closer to a front end portion of the fork compared to the primary rotatable member along an insertion direction of the fork or at a rear rotatable-member-attaching position of the fork closer to a rear end portion of the fork compared to the primary rotatable member along an extraction direction of the fork; a step detection unit (17, 18), disposed at least at a front detection-unit-attaching position of the fork closer to the front end portion of the fork compared to the auxiliary rotatable member along the insertion direction or at a rear detection-unit-attaching position of the fork closer to the rear end portion of the fork compared to the auxiliary rotatable member along the extraction direction of the fork, the step detection unit (17, 18) configured to detect a step member formed in the carriage base, wherein the control unit is further configured to lower the fork using the lifting unit in response to a detection of the step member by the step detection unit (17, 18). a body; a fork having a shape extending from the body, the fork having one portion supported by the body and another portion protruded from the body, the fork is insertable into the carriage base and extractable from the carriage base, the fork being configured to be inserted into the carriage base when transporting the carriage base using the transport apparatus; a lifting unit including one or more links; a control unit configured to control at least the lifting unit; a primary rotatable member mounted at a front end portion of the fork via the lifting unit, such that a relative position of the primary rotatable member with respect to the fork is changeable using the lifting unit, having a contact point at the point on the circumference of the primary rotatable member where it contacts the floor or step member; an auxiliary rotatable member (4, 5), having a contact point at the point on the circumference of the auxiliary rotatable member where it contacts the floor or step member, mounted such that the contact point of the auxiliary rotatable member (4, 5) is settable at a position lower than the contact point of the primary rotatable member when the fork is lowered using the lifting unit, the auxiliary rotatable member being mounted either at a front rotatable-member-attaching position of the fork closer to a front end portion of the fork compared to the primary rotatable member along an insertion direction of the fork or at a rear rotatable-member-attaching position of the fork closer to a rear end portion of the fork compared to the primary rotatable member along an extraction direction of the fork; a step detection unit (17, 18), disposed at least at a front detection-unit-attaching position of the fork closer to the front end portion of the fork compared to the auxiliary rotatable member along the insertion direction or at a rear detection-unit-attaching position of the fork closer to the rear end portion of the fork compared to the auxiliary rotatable member along the extraction direction of the fork, the step detection unit (17, 18) configured to detect a step member formed in the carriage base, wherein the control unit is further configured to lower the fork using the lifting unit in response to a detection of the step member by the step detection unit (17, 18).