Its capital is San Fernando Metropolis and borders Ilocos Sur to the north, Benguet to the east, and Pangasinan to the south. To the west of La Union is the South Porcelain Sea. 1. 1. Present are communities of Pangasinense in the south, Igorots in the Cordillera foothills, plus Chinese in the metropolis.

La Union is highly literate, with San Fernando City as the administrative, instructive, plus financial center of the region. The Harbor of San Fernando operates as an increasingly active shipping point, and the former American airbase Wallace Air Station, having been converted into a commerce and manufacturing area, helps to facilitate such commercial activity. Yet, unlike other portions of Luzon and the Philippines' two other island groupings, the Visayas plus Mindanao, La Union experiences a quite dry and prolonged dry season with little precipitation to be expected between the months of November plus May.