Long traffic queues out of Sydney and Melbourne

Holidaymakers heading out of Sydney are facing significant delays, with traffic queues of up to 10km on some of NSW's major roads.

All northbound lanes on the M1 (F3) were closed around midday on Friday after several cars and a fuel tanker crashed on the Hawkesbury River Bridge.

The lanes were later reopened, but traffic was backed up more than 10km between Sydney and the Central Coast after a second accident at Asquith.

There are also significant delays southbound on the Princes Highway, approaching Albion Park and Berry in NSW's south, and in the north on the Pacific and New England highways.

In Melbourne the gridlock was due to shopping, rather than more scenic endeavours, with traffic on the Monash Freeway off-ramp to Warrigal Road banked up.

Boxing Day bargain hunters were stuck in traffic in what has long been known as the 'Monash car park' in the battle to claim an actual parking spot at Chadstone Shopping Centre.

Traffic has since eased, however shoppers within the southern hemisphere's largest shopping centre are still suffering a gridlock of their own.