Abstract: A mobile patio umbrella support which has an upper module comprising a pair of wheels that roll over the railing much as wheels of a train roll over a railroad track and, to keep the support upright and balanced, a lower module, comprising an arrangement of casters, to block sideway motion by special fitting across the lower horizontal part of the railing. A pole, similar in size and type to the pole of a typical umbrella, and on top of which an umbrella is planted, joins the two modules of the mobile umbrella support together.