"This is a revolutionary hotel," said the guard at the Hyatt Regency Caspian, a resort hotel along the seaside in the town of Chalous that was once very popular with families from Tehran who wanted a beach vacation.

Now, however, it is not quite the same. No women are allowed in the swimming pool and, according to the guard, if any woman dares to enter the sea for a dip "we'll take her belongings from her room and throw them out of the hotel."

The religious leader of the seaside city of Nowshahr, just south of the Hyatt, appears to be slightly more liberal. He has decreed that the beach should be segregated with men and women swimming in different sections. Even so, women have to wear chadors -- the large shawls that covers the entire body -- when they go in the water.

To make sure the segregation rules are observed, both male and female revolutionary guards patrol the beach to arrest violators.

The Grand Hotel at Ramsar, a few miles north of the Hyatt along the sea, states its views firmly with a hand-lettered sign on the front door. "Women will please observe Islamic regulations and wear coverings (either a full chador or a scarf over the hair)," the sign said.

"Your veil is more effective than the blood of the martyrs in showing support for the revolution."

The big hotel appeared empty the other morning. An Iranian couple were eating breakfast, but the woman was not covered. The old section of the hotel, which housed a gambling casino in the old days, was locked up.

In front of the hotel, though, local families with women wearing chadors were parking cars to go to the beach.

Various towns seem to adopt different policies on what women should wear while swimming and whether men and women can swim together. At Astara, Iran's northernmost city along the Caspian, for instance, a police officer said men and women swim together.

"The only women who wear veils," he said, "are either very religious or very poor."

Astara, billed as a city with few if any illiterates, appears to have a far more Western view about women's rights than most places in Iran.

A banner stretched across the road said, "Women in all fields -- political, social and economic -- should have the same rights as men."

OFFICIALS ALONG THE Caspian are very nervous about foreign visitors, especially American journalists. Two of us were escorted to the police station the other day after talking to Iranians at a small cigarette and refreshment stall in Astara near the entrance to the bridge that crosses the narrow river boundary between Iran and the Soviet Union.

It took an hour and 20 minutes to get things sorted out. The governor general insisted we could not visit his border town without permission from authorities in Tehran who had said we did not need any special authority. The young English-speaking chief of the Revolutionary Guards was upset that we might have discussed the Soviet Union with someone. "You are not supposed to ask questions about Russia," he said.

Finally, we were ordered out of town. But, with typical Persian hospitality, they allowed us to eat dinner at the Astara Inn first.

THE MEN AT the refreshment stall were happy to talk about the Soviets, who come over and sell big fur caps for spending money. The shopkeeper refused to say what he pays for them, but acknowledged he sells them for about $70, making a good profit for himself. He said he stocks special red hair dye for the Soviets to take back with them.

"I feel so sorry for the Russians. They are so poor. And they can't speak their mind, even here," said one Iranian man who works with Soviet trucking firms coming over the border.

A sign across the road from the stall said, "Death to America," a common slogan here. "We say 'Death to America' and smoke your cigarettes," commented a man as he lit up a Winston, the most popular brand in Iran.

THE MAYOR OF Astara, Hassan Zahmatkesh, said there is plenty of caviar in his city. But he never touches the stuff.

Even though he can now afford to buy caviar, which he said now sells for the unbelievably low price of $13 a kilogram (about $6 a pound) he does not buy it.

"Since we were children," he said, "the rich bought all our caviar so my taste does not accept it. Believe me, I am 33 years old and I tasted it once in my life."