is a city in and the capital ofSareyn County, in Ardabil Province, Iran. Sareyn is known for its hot springs. The population is about 8000, and increases to more than 20000 in the summer because of the many tourists who go there due to the charming climate.The Sareyn springs are near an inactive volcano in mount Sabalan and its water contains sulphur particles and it is believed that it is good for bone and joint pains.
The word Sareyn in the Persian dictionary means "Spring's Outlet".
The climate and hot springs are the first attractions to tourists who travel to this region from different parts of Iran and the world.
Sareyn is also famous for its 'Ashe Doogh' (Yogurt Soups), during the busy summer periods, it is not uncommon for many of the local shops to be seen selling and preparing this soup.
Hot springs (spa) have always been in Sarein but the 1990s earthquake caused some of them to get colder or hotter. The water is heated largely by the Sabalan mountain which is Iran's second highest mountain after Damavand.
Many tourists visit Sabalan. Its most interesting feat is the 'crater' top which contains a lake of acidic water.
Sareyn is also very famous for its honey, again like the soup, many of Sareyn's shops sell honey which is produced locally by the Bee keepers of the area.