That of ‘fogheraccia’ is a very ancient custom, a propitiatory rite for an abundant harvest, which is linked to the Roman calendar, according to which the year began in March, dedicated to Mars, god of agriculture, as well as of war .
In Romagna they are traditionally called Focheracce or Fugarine di San Giuseppe, because they are held on the occasion of the feast of St. Joseph and of all fathers.
The biggest bonfire in Rimini is on the free beach in Marina Centro, near the canal port area. Here from the afternoon a market of various kinds animates the promenade with colorful stalls (from around 5 pm). 
The turning on of the fogheraccia is at about 9 pm.