Transport chiefs are rushing to remove 'dangerous' icicles that could fall on pedestrians or motorists with roads closed and routes diverted due to the threat.
In Suffolk, large icicles hanging from a bridge caused highway chiefs to close part of a busy route.
The icicles hang across the entire length of the Sturmer Road Bridge in Essex and have been seen on walking routes across the UK including down the Hopton Tunnel on the High Peak Trail in Derbyshire (pictured below).
Network Rail also used a special train to remove dangerous 5ft (1.5m) icicles dangling from the roof of a tunnel on the Settle to Carlisle line. The operator said some icicles were also cleared by hand by staff during the freezing weather conditions to prevent them from falling and causing delays.
In addition, there are fears that as the weather becomes milder, the icicles will thaw and fall on unsuspecting walkers or cars.
In London, the River Thames froze over for the first time in almost 60 years, with more snow expected.
Photographs captured the river frozen over at Teddington Lock west of London early on Friday in temperatures of -1C, before it began to thaw in the morning sunshine.
The event is thought to be the first time this has happened since the Big Freeze of 1963, the coldest winter in more than 200 years, when the river froze over around the same west London area upriver of the centre of the capital.
It came as milder conditions were forecast from Monday, marking the end of a deep freeze which will bring more snow this weekend before temperatures rise to 11-12C in the south next week.
The Thames in central London froze solid more than 20 times between the 14th and 19th century, and during five London winters, the ice became sturdy enough that "frost fairs" were held.
Markets, food sellers and performers pitched up on the river, with the last event taking place in 1814.
The period between roughly 1300 and 1850 is known as the "Little Ice Age", a natural phenomenon thought to be caused by volcanic eruptions, which saw Europe experiencing extremely cold winters.
This is now unlikely to happen again, in part due to the changing climate of the UK, but also due to the narrowing of the river during the Victorian period, which makes it too fast-flowing in central London for the water to freeze.
The UK is nearing the end of a week-long freeze dubbed "The Beast from the East 2" because of comparisons with the severe cold seen in early 2018.
On Thursday night new record low temperatures for February were recorded for England and Wales as parts of North Yorkshire dipped below minus 15C, and in Aldingham, south Cumbria, waves froze on the seashore.
The coldest UK conditions for 65 years were recorded at Braemar in the Scottish Highlands on Wednesday night, when temperatures dropped to minus 23C.
The Met Office's chief meteorologist Neil Armstrong said that temperatures would become milder next week.
“There are still some wintry hazards to get through over the next few days, with low temperatures, strong winds and further snow especially in Northern Ireland.
"On Sunday there is a risk of freezing rain over the high ground in Scotland and northern England, with further snow in the Scottish hills before turning to rain as the warm air takes hold," he said.
Skaters flocked to the frozen Cambridgeshire Fens today after the recent cold snap gave them the rare chance to enjoy the ancient sport for the first time in years.
Shallow waters in the Fens near Ely have been turned into an enormous natural ice rink and it is now a skater's paradise.
Skaters were out early this morning on the frozen flooded fields to make the most of the stunning outdoor rink.
It takes three nights of temperatures of minus six or below to form ice strong enough to skate on.
Just where in the Fens it is possible to skate varies from year to year and depends on where the farmers and river authorities have allowed the land to flood.
The last time the Fens froze was three years ago in 2018 when the Beast from the East hit the UK and the skaters managed to get a day on the ice.
The Cambridgeshire Fens were the birthplace of British speed skating and when farm hands were unable to work on the frozen land they welcomed the chance to skate for prizes.