Milford Sound is one of those places that leaves a lasting impression; I should know, since I lived and worked there for six months. Getting there, there are a couple of options varying in terms of ease and expense. One way is to drive--you can expect the drive to take two hours from Te Anau, as it is not always an easy drive and the weather will no doubt play a part. Don’t let the weather put you off, though, as the wetter, the better, trust me! If you’re travelling in winter, expect to rug up, as it will be cold, but the scenery will be amazing. Really, the drive to the Homer Tunnel isn’t too bad and shouldn’t take too long; when you get to the tunnel, however, is when the fun starts. Take some time out at the entrance to the tunnel and have your camera ready, as the mountain scenery here is brilliant, especially when it's wet. The misty rain and clouds descend on the mountains, giving you a feeling you’re in some kind of movie, and the rain coming down the large mountains creates a number of waterfalls--a sign of things to come. There should be some Kias there, as well. These cheeky birds will have no problems getting up close and personal--shyness is not an issue.
The Homer Tunnel is an experience in itself: 1.4km of chiselled rock with no lighting to speak of. Be wary of oncoming traffic, as there are no road markings either. It can be a bit of a hair-raising part of the trip for the not-so-confident driver. Out the other side, and you really will think you’re in a movie. As the road winds down the gulley, you are surrounded by huge mountains that are virtually 90 degrees straight up, and on a misty day, the clouds give the impression the mountains never stop. If you’re lucky and it’s raining (chances are good), then you begin to appreciate the hundreds of waterfalls greeting your drive to the sound. Take your time driving here, as the roads are very windy and, with the rain, can be quite treacherous. But once you reach the terminal, you’ll know it’s all worth it. Beyond the terminals is the sound--beautifully calm water with Mitre Peak standing out in the middle. Cruises leave about every 45 minutes, and you can take your pick of Red Boat cruises or Real Journeys. I'd personally opt for Real Journeys, as they have the better cruises.
Take either the Mariner or the Wanderer, as the other boats tend to cater to large numbers of Japanese, Korean, and Chinese tour groups and you really do lose the experience, as well as almost getting trampled getting to the buffet. I would recommend doing an overnight cruise on the Mariner or Wanderer and get a real experience. If you like backpacker style, then take the Wanderer; if you would like your own cabin, go for the Mariner. You will do a complete trip of the sound, heading out to sea before heading back and weighing anchor in one of the secluded inlets.
A great option when in Milford is to do some kayaking, but if you do an overnight cruise, they will include this in the package. Come sundown, the sound seems fantastically peaceful, and you think you are the only people in the world, apart from some dolphins who more often than not are keen to join in. Back on the boat, and it's time for dinner, which from memory was at about 7:30pm. The meals are nice, but you shouldn’t expect five-star dining. You can then stay up late at the bar or head to bed and be rocked asleep by the boat. The morning is an early start, but you want to be up early to catch the beauty of Milford. You do another run of the sound before stopping off at the underwater observatory. You should be back on dry land (maybe not so dry with the rain) by about 8:30am.
This is where I would splash out and book a flight using over-the-top helicopters to get me to Te Anau or Queenstown. They are about $400, but hey, the flight from Milford to Queenstown is something you’ll never forget. You won’t know whether to laugh, cry, or pee in your pants, depending on how good you are with heights and large mountains.
All in all, you could expect to pay close to $800 for the whole trip if you went full-out, but having done it and lived it, I would recommend it to anyone.