A cart having a lower frame and wheel means for moving the cart on a surface, includes a surface engaging means extending below the lower frame. When the cart engages an escalator step, the surface engaging means grips the escalator step thereby hindering movement of the cart relative to the escalator step. Normally when the cart moves on a flat surface, the surface engaging means is above the lower plane defined by the lower level of the wheel means. The surface engaging includes a saw tooth base for engaging the step. In some embodiments there is a lid for closing the shopping cart and selectively locking the basket of the shopping cart. Means is provided for selectively locking one or more wheels of the shopping cart at the same time as the lid is locked.