Occupied by a few booksellers and peddlers of souvenirs, the imposing Clock Tower Gate is set into the walls and surmounted by the yellow and white spire of the tower that gave it its name. It was once the main entrance to Cartagena. Beyond it, at the centre of a harmonious square, stands the statue of Pedro de Heredia, the city's founder. This is where elegant carriages park and wait for customers to take on tours of the historical centre.