In February 2012 in my town was a collapse when it was fell 50 cm of snow and temperatures were in deep minus most of the month, Danube river near my town was frozen.
Also, in January 2017 was very cold but with little snow only 8-9 cm, and Danube again was frozen large part of the month.
In both months Feb 2012 and Jan 2017 some people were crossing frozen Danube. It was attractive for them, no matter what they risk their lives.
Same was on Danube near my town as on this video of frozen Danube in Belgrade on January 15, 2017.