On the top of one of the Neapolitan hills, the Church of the Certosa di San Martino is a casket to one of the city's greatest treasures. Built in 1325 at the behest of the Duke Charles of Angiò, it was the mother church of the Order of the Certosini: around the cloister of the Monastery, still today, the small cells demonstrate the need for peace, peace and prayer sought by all monks. The great renovation of 1590 led, then, the church of the Certosa to be one of the largest artistic construction sites in Southern Italy: workers from Rome and from all parts of the Viceregno were charged with renewing the great church. Works that lasted for about a century, but which today open at a breathtaking glance: from the vault to the wonderful floor, every side chapel and every room is a priceless treasure. The beauty here is overwhelming from the inside out: the city skyline looks crisp and wonderful on sunny days, and poetic and fascinating even in the rain.