It's only two things for me which both have been mentioned above.
First, it's the language. Our language defines a lot of how we are. While many languages are made to facilitate communications, ours is built as a tease. Unlike most other languages, it is a virtue in Persian to be vague, indirect, open to interpretation, or even misunderstood. A lot of our cultural characteristics go back to this linguistic tendency to hide the true meaning and to imply. This is why we are not straightforward people, why we are not as honest as a society, why we don't always do or mean what we say, or say what we mean, why we consider cheating acceptable, why we personalize ethics, etc. But it's also why we can read between the lines, we understand nuance, can understand poetry like no other culture does, can cherish sadness, be imaginative or perceptive, etc.
The second thing is friends. In the west, friends are functional, they serve a purpose, and have a certain place in your life as Payandeh Iran beautifully wrote in his post. You have a friend that you go to dinner with, one to play cards with, one to play gulf, etc. In Iran you do all those things with the same friend and they occupy all your life, and so when they're not there, your whole life feels empty or full of shit depending on your perspective.
Oh, and another thing to like is that Iran has FOUR seasons!