Sylvania straddles the divide between the Lake Superior and the Mississippi River drainage systems, occupying some of the highest ground in the Midwest. As an example, many of the lakes in the park are more than above sea-level. Due to this apex position, these deep, clear lakes are primarily landlocked, fed by springs and local run-off. There are no surface streams entering the park, which is one of the reasons the lakes remain pristine and pure. For this same reason, the lakes are a bit "fragile" (low flush rates, low nutrient loads, etc.). Special fishing regulations on these lakes, including catch and release for all bass, have helped to preserve the lakes' fisheries. The Sylvania Wilderness also features of hiking trails and portages within its .