VENICE, Italy (AP) — It’s a matter of perspective. From aboard a 12-deck cruise liner, the sight of St. Mark’s Square, the Doge’s Palace and Bridge of Sighs gliding past from a cabin balcony is a breathtaking thrill.

But against the backdrop of Venice’s storied canals and Byzantine architecture, these floating condominiums present a jarring sight, out of scale and sync with 
the surroundings.

The fatal grounding of the Costa Concordia off the Tuscan coast has sharpened the focus on the largely unchecked boom of these ever-larger luxury liners, and nowhere more so than in Venice, a fragile city already struggling against mass tourism and the steady deterioration of its underwater foundations.

There’s growing clamor for an urgent rethink to the expanding cruise liner traffic through Venice’s historic centre. Critics point not only to a threat of accidents, but also air and water pollution, and the injection of an additional 2 million more tourists a year into a city already under
constant siege.

The city wants to reroute cruise ships arriving in Venice so they stay farther from St. Mark’s and other prominent monuments as a possible step toward keeping them out of the lagoon altogether. And UNESCO, the U.N. culture organization, charges that the liners cause water tides that erode building foundations and pollute waterways.