Beyond the vast sun-drenched courtyard of Esfahan’s Imam Mosque and its intricate 17th- century tiled stalactites, an audience of four Belgians and a Polish woman listened patiently to a young Iranian cleric.

Dressed in robes and Shiite turban, he explained in flawless English the differences between Islam’s two dominant sects and why the religion tells women to cover their hair. Smiling, the Belgians had photos taken with the theologian.

“We want to try and establish relationships so more people visit,” Mostafa Rastegar, who was visiting from his seminary in the holy city of Qom, said after his talk.

Foreign visitors to Iran are the most visible effect of President Hassan Rowhani’s drive to mend ties with the United States and Europe, an influx that one his deputies said generated as much as $5 billion for the sanctions-hit economy over the past year. For the first time since the 1979 Islamic Revolution, international hotel chains are now plotting a return, while European airlines are adding or restoring links with Tehran.

Between March 21 and April 20, the first month of the Iranian year, 4,594 foreign tour groups visited Iran, more than double the number that arrived in same period last year, said Morteza Rahmani-Movahed of the government’s Tourism and Heritage Organization. Iran wants to ease visa requirements for 12 countries to draw more visitors.

Saudi Arabia’s Rotana Group plans to open five-star hotels in Tehran and the Shiite pilgrimage city of Mashhad.

Austrian Airlines AG resumed direct flights to Tehran from Vienna in March. Iranian officials have been in talks with the Italian government and Alitalia SpA to increase the frequency on routes, the official Fars News Agency reported on April 30, citing the deputy head of Iran’s Civil Aviation Organization.

“The stability of the political situation will have an important impact on the economy,” Rahmani-Movahed said. “There has to be a relationship with the rest of the world.”

Among Rowhani’s first pledges after taking office last year was a pledge to improve the quality of the tourism industry and draw more foreign travelers.

Austrian tourist Edith Howorka, who had just returned from a tour of relics, said her experience had so far been “absolutely positive.”

“I like to visit countries with a very interesting culture and history,” said Howorka. “But during [former hard-line ruler Mahmoud] Ahmadinejad’s time it would never have struck me to come here. I would have felt like an enemy.”