The Lake Mistletoe car park is on the right side of Milford Road, heading north and just before Te Anau Downs. This is another relatively obscure short walking track, although better signposted than Ivon Wilson Reserve and Lake Henry near Te Anau.
You can do this as a short walk (20 minutes return) to a viewpoint above the lake or as a longer, 40-minute walk and return that includes a secondary wetland. From the car park, the walk first passes through a beech forest and then through native scrub to a nice viewpoint with a picnic table above the small lake. There are likely to be native scaup (pāpango, a small diving duck) present on the lake.
It is a sheltered area, so there is a good chance it will be calm with some reflections. It's a nice spot to take the edge off the drive.