The Aras River Valley is a narrow region that marks Iran's northern border with Azerbaijan, Nagorno Karabakh, Armenia, and Nakhchivan. The Aras River Valley boasts castles, tombs, stepped villages, and breathtaking mountain scenery, and all of this devoid of tourists. It makes an interesting day trip hiring a taxi to travel along the valley between Jolfa and Kaleybar stopping at places along the way.
Due to how remote this region is, the most logical form of transport to the Aras River Valley would be a taxi to either Jolfa or Kaleybar (not it's not in the valley, it can be used as an end point) from Tabriz. It is also possible to take a bus to Ahar and then taxi to Kaleybar.
You can enter the Iranian border town of Jolfa from Azerbaijan's Nakhchivan, crossing the bridge on foot (with a pre-arranged visa).
There are trains to the border town of Jolfa, on the west of the valley, but check exact timings as these are not frequent.
To travel along the valley you will need a taxi. Between Jolfa and Kaleybar stopping at the sites below, the journey should take 6-8 hours including lunch, so it pays to start early, especially in winter.
A taxi from Kaleybar to Jolfa or vice versa including multiple stops for the day should cost approximately 2,000,000 to 2,500,000 rials.
The Aras River Valley can be traveled east to west (Kaleybar to Jolfa) or west to east (Jolfa to Kaleybar) in a day. In addition to this there are also a few sites that can be visited in half a day to the west of Jolfa.
The entire Aras River is an international border. There are multiple police forts and military installations. Do not take photographs of anything military related as well as border crossings and be careful of what you are taking pictures of in other places (especially at Khofaafarin Bridge).