Our last stop on our New Zealand road trip was Milford Sound. There really isn't much there at Milford Sound apart from the lodge and campground (RV hookups for us) and the quay from which boat tours depart daily. On advice from the campervan people from whom we rented the vehicle I booked a powered site at the lodge (which we later found out was sold out). We also picked the smallest boat tour of Milford. The small boat was the best choice I think—not overcrowded and able to get close to the fjords (to see the waterfalls for example).
The fjords here are truly spectacular, although the weather can be somewhat unpredictable, meaning often cloudy and/or rainy, as it was when we visited. When sunny it must be really fantastic. The way the cliffs line up visually is also interesting: apparently when surveying the coastline, Cook (I think it was Cook) had missed the entry to Milford, not seeing it from the ship. One major annoyance here were the black (sand) flies. They were all over the place. They didn't bite, but were a real nuisance. The Maori legend had it that the flies were there so that tourists wouldn't stay too long and spoil the scenery.
The waterfalls pictured above was one of three (if I remember correctly) to which the boat came close to. So close in fact that at one of them I got pretty soaked when standing on the bow (just for fun). The boat also got close to some of the wildlife in the area. There were supposed to be penguins, and I think I saw three in the distance, but I wasn't sure if they were penguins or seagulls. We did get close to some seals lounging on the rocks. They found a fairly windy perch, which we were told they did to keep the flies off.