During the holy month of Ramadan or when near religious areas, you should take a little extra care not to offend.
Antiquities, photography and money can get you into trouble in Tunisia if you don't follow the local laws.
The southern desert areas are quite traditional, but the northern beach resorts (where most travelers go) are more cosmopolitan, and have a fairly European style, so you can be a little more relaxed with how you dress, but it's still important to dress modestly if you're a woman.
If you're coming to Tunisia after spending a little time in France, be aware that topless sunbathing is not acceptable in Tunisia and will cause both offence and unwanted attention.
Even in the north, Tunisian law applies to personal relationships. Like most Muslim countries, homosexuality is illegal.
It‘s technically illegal for mixed gender couples who aren‘t married to share a room together. Not much of a problem in western-style hotels, but elsewhere just say “wife/husband“ rather than “boyfriend/girlfriend“ when talking to hotel staff. A gold ring worn on the appropriate finger can smooth the way, too.
There is a reasonable amount of antiquities smuggling in Tunisia. People who try to remove antiquities without the right government permits may be arrested, and have a very long delay added to their departure.
Make very sure that if any of your purchases are antique, you obtain permission. Getting arrested when you‘re trying to leave will definitely ruin your experience.
Tunisia does not allow photographs to be taken of embassies, military or government buildings, as well as other sensitive places. If you‘re in doubt, look around for one of those no camera signs. If you see one, don‘t.
As in most countries, Tunisians don’t like to be photographed without their permission. Ask first, and you’ll likely be rewarded with a great photo, an interesting cultural interaction, or, at worst, a polite no.
Like most countries in the world, drugs are illegal. However, Tunisia tends to have somewhat harsher drug laws than western nations. Use and trafficking are obviously serious offences, but the possession of even small amounts of ‘soft‘ drugs, can result in imprisonment. In case you were wondering, yes, one joint or even a small amount of hash can result in being locked up.
Tunisia has a strong medical system for Tunisian citizens, but not for people who aren‘t. If you do require medical attention in Tunisia, be aware that private hospitals and clinics can be very expensive and payment is required immediately.
There are some interesting laws regarding currency in Tunisia, and should make sure you‘re aware of them if you‘re planning on going. It‘s actually illegal to either import or export Tunisian dollars. Make sure that you declare how much foreign currency (in cash) you‘re brining into the country, or it won‘t be leaving with you.
I you're a cash-only type of traveler, take how much money you want to spend into the country and convert it into Tunisian Dinars as you need it, and keep receipts for every money change transaction.
Those of us who use the ATM to access funds won't have a problem (although it's always a good idea to keep the receipts ATMs spit out).
If you haven‘t ever driven in a non-Western country before, driving in Tunisia will be an interesting experience. Drivers take the view that road rules, traffic signs and traffic signals are an interesting thing which bears very little relation to actually driving.
Drivers completely ignore all regulations, even when police are clearly visible. They don‘t seem to care about which side of the road they drive on half the time.
Pedestrians have right of way, which drivers generally ignore. Don't drivers to stop at pedestrian crossings or stop lights. Consequently, pedestrians take license to wander into traffic without giving much indication that they‘re about to do so. Pedestrians also enjoy running between traffic, and they do it even on major highways.
People who ride bicycles, motorcycles, and motor scooters, take this attitude to new levels and will regularly weave through traffic attempting to squeeze through incredibly narrow spaces at high speeds. It really doesn‘t help that few of these vehicles have adequate lights or reflectors, making them difficult to see even if they weren‘t driving so erratically.
Tunisia has a high number of police and military checkpoints, and if you come across one of these be sensible and approach slowly. Speeding towards a checkpoint is a good way to make several men with automatic weapons very nervous indeed. Checkpoint authorities tend to be polite to foreign travelers, but you must be ready to present photo ID upon request and they may detain you if you don‘t have it, particularly if you are near one of the more troubled border regions. Tourists must carry ID with them at all times.
If you are planning on driving outside of the urban areas, be aware that conditions are very different. Road quality can deteriorate rapidly and many roads are unpaved, full of potholes becoming covered with blowing sands.
Traveling cross-country and off-road means traveling in the desert. If you‘re not used to that, the advice is fairly straight forward and should be strictly adhered to.
For a start, make sure you‘re traveling in a vehicle that‘s capable of off-road desert travel, which means sedans are out and you really need a four-wheel drive.
Make certain you have enough water and food, and pack a little extra just in case.
Travel in multiple cars so that if one breaks down you can get back to civilisation in one of the other vehicles.
Take a GPS with you, but be aware that there are many areas in the south that have very little mobile phone coverage and all too often none at all.
Lastly, while it does get incredibly hot in summer (over 50 degrees Celsius) it is also subject to below freezing conditions at night and in winter. Even when you‘re traveling in summer, you need to bring something warm for the evening.