When you think of a reef, tropical breezes, bright fish, and warm salty seas come to mind. Green Lakes State Park, located near Syracuse, New York, challenges that stereotype. Green Lakes State Park is two lakes: Green and Round Lake. Both are meromictic, which means they are so deep in comparison to their size (195 feet and 180 feet, respectively), that there is no mixing of bottom and surface waters during autumn and spring. These ancient waters host a high potential for evidence of primitive plant and animal life. Case in point: Green Lake and Round Lake host rare freshwater reefs that are still growing. The process takes thousands of years. The lakes' bright green color (on sunny days) is attributed to these reef-building, photosynthetic bacteria. People and dogs walking along the exposed reefs have killed the top layer, so stay off.
Fortunately, there are more than 20 miles of trails with pretty views to keep you busy. None are exceptionally challenging, and all have well-marked, color-coordinated hash marks, trail maps, and placards. Hiking is permitted on all the trails. Biking, snowshoeing, and ungroomed cross-country skiing are permitted on many, but not all. Trail maps are available at the entrance and posted along the trails, and they clearly indicate what is permitted where. Round Lake is designated a National Natural Landmark.
The 3-mile perimeter loop treats you to views of both lakes and highlights the park's natural features such as the old-growth, upland forest, and the reefs. The trail is fairly flat, albeit slippery, when the snow is old. From the southern parking lot, look for the nature center. A paved path gives way to gravel and follows Green Lake. After about a mile you turn right and follow the trail over a low rise to begin the path around Round Lake. Take note of how the forest rises around you and creates the top of what feels like a basin. Round Lake is small with a 1-mile perimeter that defies its 180-foot depth. After circling Round Lake, veer right and pick up the path to complete the loop around Green Lake. An outhouse, open year-round, is located between Green Lake and Round Lake.
Green Lake is known to host flocks of Canada geese that number in the thousands. Their squawking is deafening, and at any moment the entire flock may decide to leave en mass. It's a neat spectacle, but with that many geese flying low overhead, take cover under a tree.
What's nice about Green Lakes is that the trails are reliably welcoming any time of year. Because it's so accessible (just a few minutes drive from downtown Syracuse), it does get crowded, and if you're there for cross-country skiing in the winter, prepare for hard-packed snow from the foot traffic on the more popular trails. The park is loaded with amenities. Playgrounds, campgrounds, beaches with lifeguards, indoor flushing toilets, pavilions, picnic tables, snack bar, and disc golf are just some of its luxuries. Most of these are only open from mid-May through mid-October to correspond with the campground. During this time, there is an entrance fee of $8 per vehicle. Swimming is only permitted in designated areas, and no pets are allowed in the water. An all-terrain wheelchair is available to be reserved for use.