San Francisco de Macoris, a northeastern city, has declared this coming Sunday a day of clean air, reports El Caribe newspaper. No motorized vehicles will be used in the city unless absolutely necessary. The Northeastern Catholic University, along with the Bishop of San Francisco de Macoris, is coordinating the event, the second of its kind in the city. The day is meant to encourage non-motorized exercise such as bike riding, walking and horseback riding. The event will begin at 7am on Sunday.