Hato Mayor del Rey has the municipality of El Valle to the north , the El Seibo province to the northeast and east , the San Pedro de MacorÃ s province to the south and the Monte Plata province to the west . Hato Mayor del Rey is the capital of Hato Mayor province , Dominican Republic . It is bordered on the North by the municipalities of El Valle and Sabana de la Mar , on the South by the province San Pedro de Macoris , on the East by the province El Seibo and on the West by the municipality of Bayaguana , Monte Plata .