Driving on the Milford Road is potentially very dangerous due to environmental conditions, the narrow winding road, the large variety of driving styles and varying skill levels displayed by drivers.
Please do not underestimate the time it will take to reach Milford Sound, budget at least 3 hours from Te Anau to Milford Sound, assuming good road conditions and minimal stopping along the way. If you plan on doing some of the walks described in this guide you could spend the whole day on the road.
Drive slowly and be patient with other road users, specially on the return journey, it is not a race. The best light is usually in the evening and you will miss it if you are already in Te Anau.
Keep your eyes on the road. If you are distracted by the view find a safe place to stop on the left hand side of the road. Many safe layby's are marked with a waypoint on the Milford Guide map.
Keep left, slow down and never assume anything when you are traveling around a tight corner. Vehicles are frequently sighted on the wrong side of the centre line.
Never pass a vehicle indicating right. They are indicating because they plan to turn right.
Never pass on a solid white or yellow center line. Make sure you can see well ahead of you. The speed limit is 100km per hour.
Drive to the conditions. Slow down in fog. Slow down in the rain. Be wary of ice and snow in the winter.
Check road conditions before you leave Te Anau. The Milford Road Alliance update their website at 7:30 am every morning. They will warn you if chains are required. Chains can be hired at any of the Te Anau petrol stations and from Bev's Tramping Hire.
Respect the no stopping signs after the Divide. There is a short section closed permanently to stopping due to rockfall. In the winter and spring temporary signs are used to indicate avalanche danger.
In the winter and spring, pay careful attention to road cones placed on the center line, they are used to indicate black ice. Never make assumptions on a frosty morning.
Be aware that the Homer Tunnel sometimes closes at night. There is usually a warning message displayed at the Milford Road Alliance Booth outside Te Anau.
If you are jet lagged, please consider getting some rest before you travel to Milford Sound, it is a very busy day trip. If you feel tired on the road, stop and rest. A bus tour is always a good option if you mainly want to go on a Milford Cruise.
Driving from Queenstown to Milford Sound and back in a day is not a good idea, you are looking at 10-12 hours in a car with very little time to stop. If you insist, consider one of the many bus tours available.
Do not drink and drive. New Zealand has a very low blood alcohol limit.
Take your time and enjoy your journey.