Arg Alishah or Arg of Tabriz, it’s a southest wall of citadel which backs to ilkhanid dynasty (14 century).
Some stories said it was a mosque here and in Qajar dynasty it has used as prison.
still it is a huge structure and visitors can visit it during the day.
The most important point for the building was that its vaulted ayvan was larger than the famous historic vault of Chosroes/Kisra or the Taq Kisra at Ctesiphon/Mada'in.
this monument was registered as National Monuments of Iran in 1933.
Definitely it has worth to visit.

Located at 2300 m altitude in Iran in eastern Azerbaijan, east of Oroumieh Lake and only 50 km from Tabriz, this village is characterized by its spectacular cones turned into habitat.
Kandovan comes from the Persian word Kand-e joun which literally means "digging hard, giving oneself harm". According to the inhabitants of the village, their ancestors would have dug these cones at the time of Mongol invasions of the thirteenth century to take refuge there. Formed after volcanic eruptions more than a million years ago, these cones consist of volcanic rock called tuff (mixture of ash, pebbles and sand), very malleable and can be easily dug. Thus we have a village truly linked to nature and that gives us the impression of being straight out of the earth.
Today, this village is home to 1000 inhabitants settled in 1000 dwellings. Living mainly from breeding, agriculture and the sale of local products, it is also becoming more and more touristy.
To go there :
Since Tabriz, count about 500 000 R in taxi. There are shuttles (which are actually shared taxis) from the bus station for around 250,000 R.
I advise you to spend a night to enjoy the quiet of the village once the tourists left. And to taste their dried apricots which are a treat!
There is a hotel built in 2007 in which you can sleep in cones dug or opt for a room homestay.