When Hurricane Katrina (search) hit New Orleans, the levees proved an inadequate first line of defense against flooding.

So it's clear how coastal Texas will fare when Hurricane Rita (search) strikes either late Friday night or early Saturday morning.

The massive storm may send waves over the city of Galveston's historic seawall — a 10-mile-long, 17-foot-high solid granite barrier never tested by a Category 4 or 5 storm.

Galveston Island is located on the Gulf of Mexico, 50 miles south of Houston, and is only 8 feet above sea level at its highest point. It's a barrier island sitting on a reef, averaging 2 miles in width and offering 32 miles of Gulf Coast beaches.

About 60,000 people call it home, and many more vacation on the island.

Stretching along the picturesque shoreline, the Galveston seawall is a tourist stop, gathering place and the subject of tall tales.

It was built after the hurricane of Sept. 8, 1900, still considered the country's worst natural disaster.

The unnamed hurricane took anywhere from 6,000 to 12,000 lives in what was then one of Texas' largest cities. Storm surges of up to 15 feet destroyed much of Galveston. Hotels and the waterfront were reduced to splinters. Property damage was estimated at $700 million in today's dollars.

Linda McDonald's father lived to tell her all about it.

"He said the sounds of the storm were awesome. He said it sounded like a thousand demons screaming in the night," McDonald said in an interview conducted five years ago. "And he would hear children calling for their mothers. He would hear women screaming for help."

Jan Pucket's great-grandfather died in the storm.

"There were families who lost babies ... maybe a month-old baby, and here they just had this little child and then suddenly it's gone," said Pucket, who along with McDonald was interviewed for the storm's 100th anniversary. "There's a lot of pain that I can relate to because my grandmother went through it and told me her story."

But Galveston took actions, raising the city in some areas and building the seawall.

The barrier is designed to protect residents and businesses from storm surges, but with predictions of waves 20 to 50 feet high as Rita makes her way ashore, there's no telling how the wall will fare.

FOX News' Jamie Colby and Erik Liljegren contributed to this report.