Maryland Code, Transportation § 21-1208

(a) A person may not secure a bicycle, an EPAMD, or a motor scooter to a fire hydrant, police or fire call box, or traffic control device.

(b) A person may not secure a bicycle, an EPAMD, or a motor scooter to a pole, meter, or device located within a bus or taxi-loading zone.

(c) A person may not secure a bicycle, an EPAMD, or a motor scooter to a pole, meter, or device located within 25 feet of any intersection.

(d) A person may not secure a bicycle, an EPAMD, or a motor scooter to a pole, meter, or device on which notice has been posted by the appropriate authorities forbidding the securing of bicycles.

(e) A person may not secure a bicycle, an EPAMD, or a motor scooter to any place where the securing of a bicycle or a motor scooter would obstruct or impede vehicular traffic or pedestrian movement.

(f) A bicycle, an EPAMD, or a motor scooter may be secured to a parking meter, without payment of the usual fees, if it is entirely removed from the bed of the street normally used for vehicular parking.