On top of the Quirinal Hill, in Rome’s Monti neighborhood, you can admire one of the greatest examples of Roman Baroque, created by one of the most remarkable architects of the 1600s, Francesco Borromini: the Church of San Carlo alle Quattro Fontane, which the Romans affectionately call ‘San Carlino.’ 

As a young architect in Rome, Borromini was eager to make himself known. So when he was asked to restore the small chapel belonging to the community of the Spanish Trinitarians, he offered his services for free. The chapel, dedicated to the Holy Trinity and to San Carlo Borromeo (a cardinal and the archbishop of Milan), was located between the ancient Via Pia (now Via del Quirinale) and via delle Quattro Fontane, hence its name.