Esfahan is recommended as a must-see in Iran, and I would heavily support that. Actually, I was going to zoom through Iran even faster and miss it, but I think I read in the Istanbul to Kathmandu Lonely Planet that it was the number one highlight of that whole route.
The city itself has a very laid-back vibe compared to Tehran. I think this feeling was enhanced by perfect temperature, large areas of parks, squares, and shady trees. And, the presence of river crossed by beautiful arched bridges and a tastefully planned and modernised foreshore where birds, couples, families were enjoying the sunshine.
I spent most of the time wandering on my own, meandering from sights in a way that avoided following the generic Lonely Planet walk that many seemed to follow. Again, the only tourists I saw were the same people from the one hotel. Apparently tour buses come through with mainly older passengers, but I think even this is rare. I was able to lie down and gaze at the roof, or hear my own voice echoing dozens of time in the middle of the most beautiful buildings I have seen, and not be disturbed for 15 minutes.
Rather than describe the place in too much more detail, I will let the pictures tell the story of the mosques, parks and backstreets. Check out the photos here.
Next stop, Toudeshk.