Living Good Life, With Eye On Ground

Before Hurricane Katrina, it may have been hard to imagine an entire city leveled by a natural disaster. But it happened in San Francisco, 100 years ago Tuesday.

And, reports The Early Show co-anchor Rene Syler from the "City by the Bay," experts say a similar size quake will hit there again, very likely in our lifetime.

Life in San Francisco is as vibrant today as it was in 1906, when the city was an American showcase.

Then, everything changed, in an instant.

One of the handful of survivors still alive today is Chrissie Martenstein, 108, who told CBS News, "The house shaking, to doors rattling, and the house kind of creaking, you know. It was scary. Very scary."

The numbers remain staggering: an estimated three thousand or more dead, 28,000 buildings leveled, and over 200,000 people left homeless, half the city's population at the time.

What the earthquake couldn't destroy, fire consumed. Flames raged for three days, leaving San Francisco in ruins.

But not for long.

Less than ten years later, according to city archivist Gladys Hansen, San Francisco hosted a world's fair and had a message for the world, namely that, "The city has rebuilt. It's bigger, it's better, it's taller."

Today, Syler points out, many buildings are stronger, made to withstand a major earthquake.

But the last significant temblor in the area, in 1989, still took a heavy toll, and it was 30 times smaller than the 1906 quake.

That has experts concerned.

Author and geologist Simon Winchester, who wrote, "A Crack in the Edge of the World," says the famous San Andreas fault, which runs directly under San Francisco, hasn't budged in 100 years. And it's due.