Saint-Petersburg media and public art artist, producer of cultural projects Graf (Dmitry Eroshkin) has created a collection of NFT works with the main symbols of Saint￾Petersburg. Initially the collection "Great Harmony. St. Petersburg" was exhibited from October 28 to November 3, 2018 at the 13th-century Rocco Roveresco Fortress in Senigallia (Marche region, Italy) as part of the "St. Petersburg Stories" art exhibition, as part of the "Days of St. Petersburg in Italy" festival. Computer graphics, based on the principle of the golden ratio, harmonize space and soul. The familiar silhouettes of St. Petersburg evoke emotions, which the author enhances with the help of augmented reality technology and conveys the mood of the great city in a bright, intuitively close to everyone manner.