If you are referring to St. Mark's in Venice, Italy, the Church is dedicated to him and his relics are held there.
both
YEs it has a relic of jesus
Vivaldi's father played the violin in St.mark's Cathedral in Venice.
St. Mark's Cathedral is in Venice, Italy.
The Venetians considered themselves blessed by Saint Mark because his remains were brought to Venice in the 9th century, making him the patron saint of the city. They believed that his intercession brought protection and prosperity to Venice, leading to their faith in his blessings.
St. Mark's Cathedral is in Venice, Italy.
Venice
St. Mark's Cathedral
He is a patron saint of Venice and his purported relics are buried in the basilica that is named for him in that city. Other than that, he has no connection with Venice.
His relics are in the Basilica of Saint Mark in Venice, Italy.
The remains (skeleton) of Saint Bede are in the Durham Anglican Cathedral.