Revealed: The secrets of the 50ft robo-spider

Earlier in the week, the moving sculpture - part of the city's Capital of Culture celebrations - was suspended near to Lime Street station but yesterday it was roaming the streets.

And if it's true that the scariest thing about spiders is the way they move, then a few people in this 1,000-strong crowd must have been rather spooked. 

Click to see the mechanics behind the arachnids

For while the 37-ton creature won't be seen scurrying along a skirting board any time soon, it can reach a top speed of 2mph on its articulated steel legs.

La Princesse, as the spider is known, is a giant artwork by French company La Machine. It cost £1.8million to bring to the city.

The steel and wood spider has sophisticated hydraulics which allow the dozen engineers strapped to its frame to operate its eyes, legs and abdomen.

It will continue to inflict terror and awe on the citizens of Liverpool today. Those of a nervous disposition can breathe a sigh of relief tomorrow, when it will 'escape' down the Mersey Tunnel.

The spider was ferried to Liverpool from France to go on display at a cost of £1.8million

Eric Wilson, 82, from West Derby, said: 'What the devil are they going to think of next? It's novel, I think some will like it. There's never a dull moment in Liverpool.'

His wife Dorothy, also 82, added: 'I wouldn't like to meet it in the dark. They say it's going to walk the streets but I hope I'm not down here when it does.'

And after one driver pranged his car trying to catch a glimpse of the creature, police warned motorists not to become distracted by it.

At 50 feet and 37 tonnes, the robo-arachnid wows the crowds at Liverpool Docks

Helen Marriage, producer of the show, said: 'We brought the elephant to London in 2006 and that weighed 42 tons, moved slowly through the streets and definitely did not climb buildings.

'This one's more mobile and much more flexible. It has 50 axes of movement so it moves as you would expect an insect to move.'

Funding for the beast has sparked controversy in the city.

The TaxPayers' Alliance has called the artwork an 'outrageous waste of taxpayers' money'.

Spokesman Matthew Sinclair said: 'Who on Earth would want their hard-earned cash spent on a mechanical spider? It's bonkers.'

Looming: The giant 37-ton spider clings on the side of Liverpool's concourse building