I "walked" in to Fish lake last summer. Its more like a 2 mile hike! The final leg of the hike is a very steep down hill grade. When we got there, I noticed a camp at one end of the lake with lots of kids and usual camping gear that I dont think they packed in, so there must be a shorter route. Its a float tube lake for sure, and there is another smaller lake on the trail it that looked very fishy. Search for an Olallie lake thread, and hendrixfan posted an map of the surrounding lakes.