At least one bridge on a causeway to the area collapsed, and the communications tower for the keys was no longer standing.
Dozens of coastal towns were damaged, with some reports of collapsed houses, though no deaths had been reported.
"This is a beautiful town but now it is a disaster," said local resident Sandro Sanchez, 27, walking through the main square after the hurricane had passed Remedios, in Villa Clara.
Caribbean islands hammered by Hurricane Irma's wrath
Corrugated iron from roofs was strewn in the streets alongside rubble. Lampposts were bent double, plant pots smashed and the fronds of palm trees shredded.
"You can't do anything against nature," he said. "We never had a storm wreak so much damage here. This is really a mess."
On Saturday, Irma covered most of the island, the Caribbean's largest. Its force sent shockwaves and flooding inward.
http://www.cbc.ca/beta/news/world/hurricane-irma-cuba-1.4282846By Saturday evening, the sea had penetrated two blocks over parts of the city's historic seafront boulevard, and the waters were expected to advance farther as the surge grew. Restaurants on the seaside drive pulled down their shutters and stacked sandbags against the storm.
Still, many Cubans expressed a sense of relief after the eye of the first Category 5 storm to make landfall on the island since 1932 passed over the northern keys, just grazing the mainland with its full force.
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"Honestly, I expected worse. I thought I would come back and find the roof gone," said Yolexis Domingo, 39, using a machete to hack the branches off a tree that fell in front of his house in Caibarien. "Still, it is going to be a while before I can come back to live here. The water came up to a metre high and some of the roof flew off."