A red alert remained in place in Venice Tuesday as the highest water levels in 20 years submerged 95 percent of the city and forced residents to navigate through thigh-deep water.

The flooding forced Venice's mayor to issue a travel warning, asking residents not to leave their homes and urging tourists to stay away.

“Anyone thinking of coming should think again,” Mayor Massimo Cacciari said. “These are exceptionally high waters. Don’t venture out unless it is necessary.”

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City officials said Monday that the tide peaked at 61 inches, well past the 40-inch flood mark, as strong winds pushed the sea into the city.

In St. Mark's Square, one of the city's lowest points, tourists tried to stay dry by hopping on cafe tables and chairs sticking out of the water. The water was so high that someone rowed a small speedboat across the wide square.

"It was quite an extraordinary experience," said Michel Gorski, visiting from Brussels with his wife. "We got stuck in the hotel for half a day but we didn't suffer. We were sorry for the restaurants and stores around, but there was no panic and everyone worked really hard to clean up quickly."

Workers were unable to install the traditional raised wooden walkways used during flooding because the water rose so high the platforms would have floated away too.

"There are very few streets that are water-free," admitted city spokesman Enzo Bon.

In an ironic twist, the flooding also idled the city's water buses because their boarding platforms were underwater.

Bon had no reports of damage to the city's architectural jewels, and the Culture Ministry was monitoring the situation.

It was the fourth highest tide since 1872, when the city started keeping records. The last time Venice saw such high waters was in 1986, while the all-time record was 76 inches (194 centimeters) in 1966.

That flood forced 3,000 people to evacuate and damaged many historic buildings, but largely spared the city's art — which had long ago been removed to upper floors because of frequent flooding by tides.

"In Venice, we know how to live with high water," said Bon. "Of course there are some problems, because today's was an exceptional event."

Giancarlo Galan, the conservative governor of the surrounding Veneto region, criticized Venice's center-left administration for failing to prepare for the flood and for allegedly stonewalling a long-planned system of barriers that would rise from the seabed to ease the effect of high tides.

The $5.5 billion project, called "Moses" after the Biblical figure who parted the Red Sea, has been under construction for years and is expected to be completed by 2011. The company building the barriers said, had the system been in place, the city would not have been flooded Monday.

Click here for more on this story from the Times of London.

The Associated Press contributed to this report.