This city sits perched above the aquamarine waters of the Persian Gulf, with a climate so balmy that flowers sprout from cracks in the sidewalk. Rising in the distance 16 miles south is what looks like a domed mosque, surrounded by soaring minarets.
But what to the squinting eye appears to be a house of worship is in fact a nuclear power plant, where 1,000 Russian and 3,000 Iranian workers toil daily under an oppressive sun to ready Iran's first nuclear reactor for operation by early next year.
When the 1,000-megawatt reactor is complete, it will supply a million Iranian homes with energy -- an infusion that Iran, a country with vast reserves of both oil and natural gas, says it needs to reserve its oil for export.
For years, Washington has alleged that the technological know-how and equipment that Iran acquired in building Bushehr have helped Tehran pursue a clandestine nuclear weapons program. Iranian officials offered only perfunctory denials until President Bush labeled Iran part of an "axis of evil," citing its pursuit of weapons of mass destruction.
Now, Iran appears eager to show that its activities are aboveboard, on Tuesday going so far as to allow foreign and domestic media to inspect the progress at Bushehr for the first time since 1997.
Antiaircraft artillery installations dotted the periphery of the plant, and workers in hard hats milled about the complex's 30 dusty buildings. Small packs of speckled goats roamed the grounds.
Signs in both Russian and Farsi instructed workers to exercise caution; the meaning of various displays of graffiti, such as a giant pair of red lips spray-painted near the center of the site, was less clear.
Bushehr, however, is the least controversial of Iran's burgeoning number of known nuclear facilities. The plant is a type used in many countries to generate energy for civilian purposes.
Although the spent fuel from the plant could be reprocessed into weapons-grade material, that would require a reprocessing plant, which Iran is not believed to have.
Iran disclosed Bushehr to the U.N. nuclear watchdog, the International Atomic Energy Agency, several years ago. The plant is under agency safeguards, including monitoring by its inspectors. Once the plant goes into operation, it will be under 24-hour surveillance by agency cameras.
More disconcerting to IAEA officials, the United States and other countries was the discovery through satellite imagery last summer of a large uranium enrichment facility near the central city of Natanz.
The Natanz plant, which IAEA chief Mohamed ElBaradei visited for the first time last month, relies on centrifuge technology to concentrate natural uranium, whose crucial isotopes are present in tiny quantities. To generate energy for civilian purposes, the uranium must be concentrated until the fissile material reaches a level of 3% to 5%, according to Leonard Spector, director of the Center for Nonproliferation Studies' Washington office.
Uranium must be concentrated many more times to reach the 90% level required for use in nuclear weapons. Reaching the 3% to 5% level is considerably time-consuming; however, after that, the rate of concentration accelerates.
The fear is that Iran could stockpile uranium concentrated at low levels, and when it wanted to make weapons-grade material, easily complete the process, Spector said.
Iran is a signatory of the Nuclear Nonproliferation Treaty, and none of its disclosed activities -- or even the failure to declare the existence of the Natanz facility -- violate the agreement.
However, U.S. officials and nuclear experts now believe that Iran probably produced weapons-grade material while testing the technology for its Natanz facility. Even the production of a tiny quantity of fissile material would be a violation of the treaty.
Tuesday, however, Assadollah Sabouri, deputy director of Iran's Atomic Energy Organization, denied that there has been any violation of the treaty. "We have no problems in observing the NPT," he said.
After ElBaradei's recent visit, Iran had said it would consider signing an additional protocol that would allow wider inspections. But Sabouri suggested Tuesday that Tehran is not inclined to agree unless other nations offer more assistance for Iran's nuclear programs.
"They say accept more commitments," he said. "Fine, then come build reactors for us."
But foreign technical help -- particularly Moscow's cooperation on the Bushehr plant -- remains the source of some controversy.
While the U.S. has criticized Russia's assistance, Moscow has defended itself by noting that it has set up a process to safeguard spent fuel from the reactor: Moscow has promised to supply the reactor with fuel for 15 years, on the condition that Iran return the spent fuel every six years. But Sabouri said Tuesday that the agreement for the return of the fuel has yet to be signed.
The Bush administration is pointing to the failure to detect the Natanz program as an example of the limitations of the IAEA's ability to monitor nuclear activities.
"We have seen this week Iran has got a more aggressive nuclear development program than the IAEA thought it had, and surprised the IAEA," Secretary of State Colin L. Powell said on CNN on Sunday.
IAEA officials have refrained from responding directly. Agency officials say they are moving as quickly as possible to learn about the recently disclosed Iranian nuclear operations. They note that they rely on information from U.N. member nations to help them determine when countries might have a clandestine program.
Nonproliferation analysts say that the IAEA has limitations but that it appears to be doing what it can under the circumstances.
"There is some justification to be concerned that they missed something again," said Spector. "We don't quite know how much they missed, but they are the only game in town."
Moaveni reported from Bushehr and Rubin from Amman, Jordan.