ST. PETERSBURG, Russia — The Scarlet Sails celebration is a rite of passage both figuratively and literally. Every year, tall ships with glowing red sails make their way down the Neva River in St. Petersburg to honor recent school graduates as they set out on their journey into adulthood.

Enormous, happy crowds gathered along the river banks to watch the ships on Friday and Saturday, along with an elaborate fireworks show. The pageant’s colors were augmented by the deep blue glow of the night sky, which never becomes completely dark over the northern city during the summer.

Recent graduates flocked from throughout Russia for the celebration, embracing each other, tossing their fellows in the air and clambering onto windowsills and door frames to watch the passing ships.

The celebration dates to Soviet times, in 1968, and is rooted in the earlier romantic fantasy novel of the same name by Russian author Aleksandr Green, which was turned into a popular movie in 1961. The book tells the tale of a poor girl of whom a mysterious figure prophesies that her suitor will come in a ship bearing red sails to take her away into a wondrous future.

The event was stopped in 1979, to be revived in 2005 as a major tourist spectacle drawing hundreds of thousands of people and including music and other performances.