The Christmas and New Year sales season has seen bargain hunters arriving at the Bluewater shopping centre, in Kent, in the middle of the night.
Bluewater said the long, snaking queues were a "phenomenal sight"
Some sales-hungry shoppers began queuing as early as 0100 GMT on Wednesday, according to the centre.
About 2,500 people lined up for half a mile through Bluewater to get into the Next store when it opened at 0500 GMT.
The centre's Tim Hollands said: "It's what we were expecting. This is typically our busiest day of the year."
The Next store opened five hours before the shopping centre itself
Up to 75,000 shoppers passed through the centre's doors on Boxing Day, but as many as 100,000 more than that were expected on Wednesday.
Head of marketing, Linsey Wooldridge, said shoppers at Next were having to queue at the tills for up to two hours to pay for their goods.
Extra traffic marshals were on duty in Bluewater's nine car parks, while there were also additional security and customer services staff inside.
Shoppers across Britain are expected to spend more than £30bn over the festive season, slightly more than in 2005.