But the situation was reversed by Thursday afternoon, as holidaymakers were leaving the city for the Anzac Day long weekend and a number of serious accidents closed roads.

Traffic volumes on many of the city's major roads dropped between 1 per cent and 8 per cent earlier in the week.

This might not sound like much but, according to traffic experts, it was enough to make a large difference to the experience of driving.

“If you've been driving around Sydney this week, it’s blissful,” said Phil Akers, the general manager of the Transport Management Centre.

“It’s not a huge difference in volumes - it is only a 5 per cent reduction on most of the roads - but it doesn’t take a lot to make a very marked difference.”

The fall in road traffic – with schools on holiday, and with many Sydney residents having chosen to take this shortened week off work – is less pronounced on the city’s motorways.

Volumes dropped only 1.3 per cent on the always-clogged M5 East motorway, and just 2.3 per cent on Parramatta Road, which Mr Akers described as essentially an extension of the M4 motorway.

“The motorways are carrying more of your heavy commuter stuff, whereas the arterial roads carry that but also a lot of local traffic,” Mr Akers said. On holidays, people tend to avoid peak periods when driving locally.

On Wednesday, about 8 per cent fewer cars drove along Victoria Road at Rozelle compared with a fortnight earlier; about 6 per cent fewer cars drove along the Pacific Highway at Chatswood compared with the fortnight earlier.

The situation is also expected to reverse as holiday-makers and day-trippers return ot the city on Sunday.

At the northern and southern exit points from Sydney last weekend, traffic built up for kilometres as residents left the city for Easter.

On Thursday afternoon, motorists faced lengthy queues when a multi-vehicle accident closed all northbound lanes of the M1 Pacific Motorway at Mount White just before 3pm.

For those heading south, the worst bottlenecks, according to the Transport Management Centre, are either near Kiama on the Princes Highway or when travelling through towns like Milton, Ulladulla and Berry, which do not have a motorway bypass.

A fatal car crash on Bolong Road in the Southern Highlands closed that road between Shoalhaven Heads and Bomaderry on Thursday. A 72-year-old man died after a head-on collision.

Travelling north, conditions at a number of notorious bottlenecks have eased due to road upgrades on the Pacific Highway. The highway near Kempsey and Bulahdelah has improved; the longest queues last weekend were near Byron Bay, coinciding with the Bluesfest music festival.

Charles Casuscelli, the member for Strathfield and a former head of the Transport Management Centre, said he felt that traffic in Sydney this week was the best it had been for years - but he could not be sure why this was the case.

"I was genuinely surprised at the extent of the freedom of movement in the past few days," Mr Casuscelli said.

"I can move around Sydney now far better than I did last year at the same time."