Which 'march across the ice' had comparatively the most casualties?

Question

I'm wondering whether a 'march across the ice' has ever ended in a catastrophe. These events are typically described as "risky", "daring", "bold", and "exceptional" (various sources), and yet all the examples I know of (noted below) were successful. This success seems to have been a direct consequence of the planning that went into these events, so it is perhaps not unsurprising that the events succeeded. Therefore, instead of wondering whether a 'march across the ice' has failed, I'd like to know which one ended in the worst results: which 'march across the ice' had comparatively the most casualties due to the nature of the endeavour?

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Definitions

'March across the ice': an endeavour where a military force decides to cross a frozen body of water.⁽¹⁾
Comparative casualties: percentage-wise of the whole force involved in the crossing (as these may be very problematic, descriptive answers are welcome without specific casualty counts).
Nature of the endeavour: Something that can only have happened because of the march happening on a frozen body of water, either related to natural causes, such as ice breaking up or a snowstorm, or human-devised causes which take advantage of the natural environment, e.g. by causing the ice to break up.⁽²⁾

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Examples

The examples I know of (but it is likely there are more such events, especially in non-European places):

• De La Gardie's crossing of the Gulf of Finland in 1580 against the Russians in Wesenberg and Tolsburg—detail is lacking;
• The March Across the Belts in 1658 where Karl X Gustav sent Dahlberg to check the ice who confirmed that the cavalry and artillery could pass, after which the Swedish crossed the frozen sea and forced the Danish surrender—mention is made that the army actually marched through water (that must have been... scary);
• Washington's Third Crossing of the Delaware in 1777 which seems to have gone very well despite adverse weather;
• De Tolly's march against Umeå in 1808 was part of a three-pronged Russian advance against Sweden in which de Tolly crossed the frozen Gulf of Bothnia and took Swedish Umeå—a source I've been unable to track down qualified this as 'very harsh' with several problems;
• Kulnev's march against Stockholm was another part of the three-pronged Russian advance, but was cut short—no specific detail is given.

There is an example of a Swedish force being scattered and destroyed in a regular winter storm—the Carolean Death March—but that was an on-land retreat so it doesn't count.

To compare these frozen marches with desert crossings, for all the successful ones there's Herodotus' narrative of the Persian army lost in a desert (at 100% casualty rate in Herodotus' book), which, even if apocryphal, is a good warning.

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_{(1) We should have sources that indicate the march actually took place across the ice, so that I'm reluctant to consider the Lithuanian force which engaged its opponents on the frozen Moon Sound as we don't know where they started out from. (2)However, merely having two armies meet and slaughter each other on a frozen sea is not sufficient.}

Answer 1

During the Soviet-Finnish Winter War, the Soviets attempted to outflank the Mannerheim Line by crossing the frozen Gulf of Finland in the south and Lake Ladoga in the north.

On February 10th and 11th, the Soviet flanking maneuvers in the Gulf of Finland were caught in the open by Finnish coastal artillery.

...the Russians [Soviets] tried for the first time to outflank the line by sending powerful infantry columns on a long, curving march across the thick ice. Before these forces could come ashore behind Finnish lines, however, they were spotted and taken under fire by the coastal batteries in the Koivisto sector, paritcularly the six-, eight-, and ten-inch weapons emplaced near Saarenpää, on Koivisto Island, and at Humaljoki on the mainland... The six- and eight-inch weapons were supplied with shrapnel shells that were fused to detonate in airbursts over the heads of the Russian columns like gigantic shotgun blasts. The heavy coastal battery, armed only with shells designed to pierce a battleship's armored deck, could not cause that kind of damage with their elephantine projectiles, but the enormous weight and velocity with which they struck tore great holes in the surface ice, so that each successive strike enlarged the fractures until they turned into chasms. Hundreds of men drowned in the cold black waters, sucked down by the weight of their gear, or froze to death in a matter of seconds as they tried to swim on solid ice.

On the 12th, they tried again at Saarenpää and nearly made it.

Screened by a thick ground fog, two companies of Red [Soviet] infantry managed to sneak across the ice and get to within fifty meters of the coastline before being spotted by a small security patrol. These opened fire with small arms and pinned down the attackers until an observer with a field telephone could arrive on the scene and direct the gun laying of a six-inch battery of naval rifles, the only weapons that could depress low enough to hit such a close target. By the time the ground fog had burned off, the coastal battery was trained down the Russians' [Soviets'] throats at point-blank range. The attacking force was torn to pieces by its bombardment; not a man set foot on the Finnish shore.

They tried again with some field artillery.

Later that same day the Russians sent 76.2 mm. field guns out onto the ice to lay down a barrage, along with twenty-five medium tanks to overrun the defenders while they were still pinned down. Disregarding the shells bursting all around their emplacements, the Saarenpää gunners coolly waited for the armored formation to fill their sights, then opened up a blistering barrage, keeping at least three shells in the air simultaneously until there were simply no more targets to engage. All twenty-five tanks were ablaze or had sunk through holes in the ice.

Similar attempts to outflank Taipale on the Finnish left played out on Lake Ladoga.

...large formations [of Soviet infantry] moved out to turn the Taipale flank by marching across the ice of Lake Ladoga. There, just like the men who tried to storm Saarenpää, they were slaughtered by the shore batteries. The fighting rose in intensity and reached a grim climax on February 14, when in the space of less than four hours, 2,500 Russian [Soviet] infantry were cut down on the ice around Taipale.

Source: "A Frozen Hell" by William R. Trotter, pp 219-220.