Carnival crowds arrive before Venice entry fee kicks in.

Venice streets and bridges were thronged with tourists over Valentine's weekend, as carnival celebrations got underway, raising fresh concerns of overcrowding in the Italian city.

The controversy was sparked by viral video footage of crowds barely able to move on Ponte Rialto as visitors jostled for a view of the spectacular carnival water parade along the Grand Canal below.

Around 150,000 tourists poured into the city over the weekend, according to Corriere della Sera newspaper, attracted by a "perfect mix of Valentine's Day, sunshine and Carnevale".

Amid appeals from local residents for crowd control measures, police sought to downplay the human traffic jam, saying it lasted just a few minutes, and that the city was well prepared for the crowds.

"The situation was under control and there were no critical moments, we knew that many people would arrive for Carnival and we had been preparing for a long time", says the city's prefect Darco Pellos told the Corriere.

This year's carnival festivities, which are dedicated to Casanova on the 300th anniversary of his birth, kicked off on Valentine's Day and will conclude on 4 March.

The latest outcry over crowds of tourists in Venice comes as the city prepares to expand its day-tripper entry fee system, which will be in force on 54 days between 18 April and 27 July, mainly on weekends and public holidays.

The €5 visitor fee will be increased to €10 for tourists who book less than four days in advance, however the system does not apply to the city's residents or visitors staying overnight.

Photo Corriere delle Alpi