The Foreign and Commonwealth Office (FCO) advise against all travel to:
within 100km of the entire Iran/Afghanistan border
within 10km of the entire Iran/Iraq border
the province of Sistan-Baluchistan
the area east of the line running from Bam to Jask, including Bam
During a demonstration on 29 November 2011 the British Embassy in Tehran was attacked and set on fire. The Embassy remains closed. The consular support the British government can offer is therefore very limited.
If you need routine consular assistance in Iran you should contact the Foreign and Commonwealth Office on +44 20 7008 1500.
If you need emergency consular assistance, including an emergency travel document, you should contact the Swedish Embassy or the Embassy of any other EU Member State in Tehran. See Safety and security
There is a general threat from terrorism. See Terrorism
Take out comprehensive travel and medical insurance before you travel.