Our Lady of Mercy Cathedral, La Serena, Catholic cathedral at Plaza de Armas, La Serena, Chile.

Our Lady of Mercy Cathedral is a neoclassical Catholic church on the Plaza de Armas of La Serena, Chile. It measures 60 meters long by 20 meters wide, with three central sections and a single tower whose upper part was designed by French architect Eugenio Joannon in 1912. The walls are cut limestone from Peñuelas, and the interior has three barrel vaults over a black-and-white marble floor laid like a chessboard.

The parish church La Matriz-El Sagrario, the city's first temple, stood here from 1549; in 1741 it was recorded as a single nave 50 m long and 10 m wide with seven altars and a tower to the right. It was demolished in 1840, and from 1844 the French architect Juan Herbage directed the present cathedral, reusing much of the old material and completing it in 1856. The upper part of the tower was designed by the French architect Eugenio Joannon in 1912.

The cathedral faces the Plaza de Armas, the main square of La Serena, and acts as a natural gathering point for residents and visitors alike. Religious services take place regularly, and the square in front fills with people throughout the day.

The cathedral is right on the Plaza de Armas and easy to reach on foot from anywhere in the city center, via Los Carrera or Cordovez streets. It is open daily and visitors can walk in freely to see the interior.

When the current building was constructed, materials from the original 1549 church were incorporated into the new structure. This means parts of a colonial-era building are literally embedded in the 19th-century walls you can see today.