Updated

The leafy Green Zone (search) is touted as the safest place in Baghdad, but the U.S.-guarded enclave that spreads along the banks of the Tigris River in the heart of the capital has never been immune from violence.

Even before Thursday's deadly bombings at a market and a cafe inside the fenced-off four square miles, the zone was a regular target of insurgent mortar attacks and several car bombs exploded at its gates. In recent weeks, U.S. authorities had warned Americans to avoid walking alone, especially at night, and urged them to stay away from the cafe and bazaar that were the interim government, occupation officials and foreign contractors as well as the homes of thousands of average Iraqis.

It is centered on Saddam Hussein's mammoth Republican Palace and there are dozens of smaller palatial buildings, houses, office buildings and a hospital once used by high-ranking members of the old Baath Party (search) regime.

Surrounded by 13-foot-high concrete walls, razor wire, sandbag bunkers and guard posts, the zone also is an enclave of the Western lifestyle.

Women in shorts often jog along tree-lined avenues, and off-duty soldiers lounge by the pool. The Green Zone Cafe (search), which was attacked Thursday, and two Chinese restaurants had been packed with Americans and other foreigners in the evenings until the warning was issued last week.

Everything from pornographic movies to mobile phone accessories are on sale at the local bazaar. And for the 5,000 or so Americans hunkered down in the zone, there are direct phone connections to the United States.

One problem is a lack of space. Dozens of trailer parks are scattered around the zone, shielded by sandbags to guard against mortar shells and rockets.

The American planners who drew the Green Zone perimeter had to include hundreds of middle class homes because they were near important government buildings that couldn't be left out. Many of those people aren't happy about their American neighbors.

"There aren't any kind of friendships between Iraqis living in the Green Zone and the Americans," Umm Omar, an Iraqi housewife who lives in a compound of 50 buildings said recently. "Our only contact with the Americans is at the checkpoint when we enter and leave."

She said it takes 10 minutes to leave the zone but can take up to three hours to get back in, as residents pass through five sets of security checks, two manned by Iraqis and three by American soldiers.