hi.

one of thing that is so important for tourist is:

where can they exchange?

these are some tips for traveler who come to IRAN.

1)Do not exchange in  the airport.if you need rial to take taxi and you are in the airport,no problem....exchange but small amount of money. 

2)do not exchange in banks all over city.

3)do not exchange with stranger who sells and buys dollar,euro,.... in the street.these people are not secure.but if have a guide there is no problem exchange with these people.but I am not totally agree with this way.

the best answer is EXCHANGE SHOP all over IRAN.their exchange rate are good and they are completely secure.keep in mind before you go to shop check exchange rate in the internet.the exchange shop have small wage that they decrease from your money.

It is better to have this currency in IRAN:

1)Usa dollar

2)Euro

3)British Pound

keep in mind you can change other currency but you should search a little more to find a exchange shop that change your money.