Hundreds of nude swimmers have brought a cheeky end to Hobart's Dark Mofo winter festival with a chilly swim in the River Derwent.

About 1,100 people registered for the event and nearly 700 turned out to plunge into the water at Long Beach in Sandy Bay.

The temperature hovered around 12 degrees Celsius and it was a similar temperature in the water — eight degrees cooler than Sydney's Bondi Beach.

Many of the swimmers were drenched well before the swim due to rain.

Swimmers were all smiles after their winter solstice dip. ( ABC News: Pablo Vinales )

Alyssa Hawley said the plunge was well worth it.

"I just thought it would be invigorating and I have done a winter swim before and it was pretty fun," she said.

"It was pretty freezing but you don't really feel it because everyone else is running in and you're kind of caught up in the moment ... it's cold but it's not, like, nuts."

Dark Mofo's executive producer Kate Gould said the wet conditions both in and out of the ocean did not deter too many.

"We're absolutely staggered," she said.

"This event has become a phenomenon each year in Tasmania, 670 people have turned out this morning to brave this incredible weather.

"We often get a drop off, but I have to say the drop off has been less this year because we have die-hard fans of this event."

A couple dries off after swimming in 12 degree waters at the Hobart nude swim. ( ABC News: Pablo Vinales )

The solstice swim marks the shortest day of the year and the end of the Dark Mofo winter festival which featured music and art installations around Hobart and further afield.

The festival has been running since early June and attracted 50,000 people to the event's Dark Park alone.

Final figures are yet to be released but the winter feast also attracted huge crowds.

Dark Mofo is the winter version of the summer festival run in conjunction with the Museum of Old and New Art (MONA).