Unfortunately I have upload speeds of about 10 k/s, and PCs are slow, so posts will be briefer, and have less pictures. I'm sorry.
If I was ever to paraphrase hospitality, "Iranians" would be the word of my choosing. To travel this country without being invited you would not only need to be an utter misanthrope (that alone won't help), but also go far out of your way to avoid all the welcoming people you'd meet.
Iranians are already quite sociable and friendly amongst themselves, but once you are recognized as a foreigner, their helpfulness and interest knows no bounds. Even with little or no knowledge of a foreign language they will show you around, invite you for dinner (in their own homes) and pay for your taxi. Not a day passes here without meeting some new people who go out of their way to improve your opinion of Iran and its people. I have drunk at least my own body weight in tea and sugar, sponsored by caretakers, engineers, tour guides and students who were eager to have a chat and a souvenir picture. Sometimes it becomes even mildly annoying, as some of them are so happy talking to foreigners that they will not let you go for hours and insist on taking you everywhere or sending you a text message every day or so. (To my Iranians who read this: this does not include you, don't worry.)
With the spontaneous friendship often comes a physicality that I'm not used to as a northern European. Walking hand in hand is common among (heterosexual) men, and when interacting with Iranians, you will need to get used to frequently getting hugged and touched.
Befriending women, contrary to my initial belief, is no problem (frequently even easier, as they seem to be more fluent in English), and no one seems to mind or even notice. Many of the warnings from guidebooks seem to be exaggerated or only useful in remote and very conservative areas.
Anyone remember the classic game Frogger? For those who don't, the goal is to cross several lanes of a busy street as a frog without getting run over. This is exactly how being a pedestrian in Iran is like. Iranian driving is...creative. Having been to China I'm used to red lights only having aesthetic function, and horns being the main medium of ensuring a consistent traffic flow. Iranians take the concept one step further, however. Why stick to three lanes when they can easily be made four? Reversing on a motorway to catch that missed exit? No big deal. Driving while on the phone? Sure, but only with a sandwich in the other hand. No room on the road? Well there's always the sidewalk.
So how can you avoid meeting an inglorious demise at the hands of an Iranian taxi driver? The answer is as simple as it is uncompelling: just start walking, slowly but steadily and entirely rely on the drivers to navigate around you. Do not stop, and never, never make a hasty retreat backwards. The optimum breaking distance here is about 3 to 5 inches (even less for the ubiquitous motorcycles), and shying backwards is a sure way to get hit by the vehicle passing behind you. Thankfully Iranians are used to this traffic and are exceptionally good drivers (in the vehicle maneuver ability sense), so used that they don't even swear when someone decides to change direction into a one-way street (the wrong way of course) while at the center of a four lane crossing.