Thousands of people came to Lake Phalen on Feb. 21, 1986, to watch the historic centennial ice palace come crashing down. It took just half an hour for two months of work to crumble.

The demolition of that 128-foot structure was one of the most memorable St. Paul Winter Carnival ice palace demolitions in recent history, but the 36 ice palaces from 1886 to 2004 didn’t always meet a dramatic end.

In the old days, they were just left to melt, said Larry Millett, author of “Lost Twin Cities” and former Pioneer Press architecture critic.

Later on, demolitions were required by insurers, Millett said.

Organizers didn’t want to take the chance of people crawling around on melting ice palaces and getting hurt, said Hampton Smith, a reference librarian at the Minnesota Historical Society.

An insurer was difficult to find for the centennial ice palace in 1986 — originally planned at 150 feet.

“Insurers were not standing in line for the opportunity to write a policy for a structure built of ice,” Millett wrote in 1986.

The carnival association needed to provide the builder a $1 million errors and omissions liability policy that didn’t come through until weeks before the carnival.

On the day of the castle’s demise, the Vulcans hosed down the palace with red-dyed water before contractors came in with a wrecking ball. The words “10,000 lbs palace buster” were scrawled across the wrecking ball, which took down the palace’s tower in two swings.

Don Trudeau of Minnesota Lumber and Wrecking Corp., dressed as a Vulcan, operated the 5-ton ball.

But it bounced right off the rest of the structure at first, recalled ice palace historian Bob Olsen.

In 1992, there were concerns about ice for the palace being harvested from one body of water and left to melt into the Mississippi River.

Algae and other species could be introduced into the watershed, so it had to be bulldozed so it melted into the ground instead of flowing directly into the river, Olsen said.

This year, the Winter Carnival features a Royal Courtyard, reminiscent of the old ice palaces.

With only 1,000 blocks of ice, demolition will be a much simpler task.

Contractors will break apart the courtyard and use skid loaders to haul the ice to a location where it can melt, said Rosanne Bump, president of the St. Paul Festival and Heritage Foundation.

The details of how they will break it apart or where they will take the ice still were being worked out as of Wednesday, Bump said.

The first three ice palace demolitions from 1886 to 1888 were a spectacular sight, Olsen said.

“They did up the end of carnival the right way. They burned them down, lit gigantic fires inside of them that caused some structural damage and then let them melt,” Olsen said.

Plenty has been written about how ice palaces were built, but not so much about how they went away, Smith said.

“The carnival ends and everyone forgets about it,” he said.

Olsen listed some other highlights:

— 1896: The ice palace was under construction when it was destroyed by a thunderstorm and put the carnival in bankruptcy.

— 1942: An ice palace was being built in Highland Park. There wasn’t a lot of ice because of warm weather. Easterly winds and the warmth brought the building of the palace to a halt. Demolition workers destroyed it with dynamite.

— 1947: As was the case five years earlier, construction of an ice palace was started but then halted because it was too warm to continue. The structure was demolished.

Katie Kather can be reached at 651-228-5006. Follow her at twitter.com/ktkather.

Copyright 2015 Pioneer Press.