Question:

I understand the general advice when travelling to Iran is to take all the cash you will need in hard currency and exchange it there. How do people manage this if they plan on travelling overland to Iran from countries which don't have hard carrency (eg Pakistan in my case)?

Answer:

Due to the economic embargo, you cannot use credit cards or ATMs. So cash is the only way to go. Iran is cheap but bring plenty of cash since if you run out of it, you can do nothing.
Be aware that in Iran people use two currencies. The currency in Iran, or the money used, is called Rial.
As a tourist bring only cash to Iran because no kind of cards and cheques are acceptable in Iran. Dollar and Euro are both acceptable in Iran and can be exchanged to Rial in the banks, exchanges and airports.

Check the cheapest Iran tours.