An anonymous traveller — clearly moved by what they saw — dashed off four words that say everything: "Such beautiful Catholic churches here in Montreal," scrawled in looping blue ballpoint on the back of this linen-era PECO card in June 1950, capturing a moment of genuine wonder at the city's ecclesiastical grandeur. The front shows the Notre-Dame Basilica of Old Montreal in its characteristic ochre-gold stone, its twin Gothic-revival towers — named "Temperance" and "Perseverance" — flanking an arched entrance portal, with a small public square and monument visible at street level. Number 51 in the PECO series of Montreal views, this is a canonical image of one of Canada's most visited landmarks, built between 1824 and 1829 to designs by Irish-American architect James O'Donnell. The handwritten message and 1950 date add social-history charm that unused examples simply cannot replicate.