A head-mountable display comprising: a main body in which a display is built; a wearing band extending from the main body and having a shape enclosing a head of a user during use, the wearing band comprising a right-side extending section and a left-side extending section; a movable section linking the right-side extending section with the left-side extending section, the movable section being movable relative to the right-side extending section and the left-side extending section in a retracting direction in which the movable section moves closer to the main body, and in an extending direction in which the movable section moves further from the main body; a locking mechanism capable of switching the wearing band between an unlocked state in which movements of the movable section in the extending direction and the retracting direction are allowed and a locked state in which a movement of the movable section at least in the extending direction is restricted; and a first manipulating member arranged on the movable section, the first manipulating member being a rotary member being able to be rotated by the user, wherein the movable section is configured to be moved in the retracting direction when the first manipulating member rotates, wherein the movable section includes a housing defining an inner volume, wherein: the surface of the housing includes an upper hole and a lower hole; the first manipulating member is disposed at least partially within the inner volume of the housing; the first manipulating member extends from within the inner volume of the housing through the upper hole such that a first portion of the first manipulating member is exposed; and the first manipulating member extends from within the inner volume of the housing through the lower hole such that a second portion of the first manipulating member is exposed. a main body in which a display is built; a wearing band extending from the main body and having a shape enclosing a head of a user during use, the wearing band comprising a right-side extending section and a left-side extending section; a movable section linking the right-side extending section with the left-side extending section, the movable section being movable relative to the right-side extending section and the left-side extending section in a retracting direction in which the movable section moves closer to the main body, and in an extending direction in which the movable section moves further from the main body; a locking mechanism capable of switching the wearing band between an unlocked state in which movements of the movable section in the extending direction and the retracting direction are allowed and a locked state in which a movement of the movable section at least in the extending direction is restricted; and a first manipulating member arranged on the movable section, the first manipulating member being a rotary member being able to be rotated by the user, wherein the movable section is configured to be moved in the retracting direction when the first manipulating member rotates, wherein the movable section includes a housing defining an inner volume, wherein: the surface of the housing includes an upper hole and a lower hole; the first manipulating member is disposed at least partially within the inner volume of the housing; the first manipulating member extends from within the inner volume of the housing through the upper hole such that a first portion of the first manipulating member is exposed; and the first manipulating member extends from within the inner volume of the housing through the lower hole such that a second portion of the first manipulating member is exposed. the surface of the housing includes an upper hole and a lower hole; the first manipulating member is disposed at least partially within the inner volume of the housing; the first manipulating member extends from within the inner volume of the housing through the upper hole such that a first portion of the first manipulating member is exposed; and the first manipulating member extends from within the inner volume of the housing through the lower hole such that a second portion of the first manipulating member is exposed.