There are places to enjoy the outdoors without leaving the city limits. But if you're in a mood to try southern Illinois, it has treasures to offer. So do places nearby.
Illinois Natural History Survey researcher and author ("Hiking Illinois") Susan Post says "the main requirement I have for a hike is that it includes something interesting to observe. In winter, one might think it would include nothing but tree silhouettes and the occasional deer. If you know what to look for, however, there is plenty to see."
Kanter says any nature area you go to will have something of interest. At River Bend Forest Preserve near Mahomet, for instance, "they have a long season there in terms of open water. Birds are always looking for open water."
Birds are scarce now, but you can still spot a bald eagle on the water now and then, he said, especially at sunrise or sunset.
Post writes in an email that Kickapoo State Park  near Oakwood is an excellent place to spot insects.
"In winter, the main attraction for me at Kickapoo is the bridges," she wrote. "They are gathering places for winter stoneflies, a unique group of insects that appears from November to March. The stoneflies congregate in places exposed to the sun's warming rays. The park's concrete bridges are beacons of warmth to a stonefly; with a bit of searching you can see them crawling, interacting with each other, and even mating."
Kanter also loves Kickapoo in winter.
"Most of the trails have gravel on them. It's a different experience from the summer. In winter, you can see how many other people are there," he said.
At least one pair of bald eagles is nesting along the Middle Fork River , he said.
Also in Vermilion County is Forest Glen Preserve 's Willow Creek Trail.
"The trail to hike if you are searching for the state's earliest blooming plant — skunk cabbage — is Willow Creek," Post wrote. "The trail leads to a Howard's Hollow Seep (a habitat that is permanently wet, yet cloaked in vegetation). Look for the ruddy, yellow-streaked hood of this plant as it bravely pokes through the moist earth in late winter. Skunk cabbage generates its own heat to melt through snow and ice and maintains warm temperatures inside the hood. The trail is 1 mile long."
The UI's Allerton Park  is great for birders, Kanter said.
"Birders go to check some stands of evergreens; seed-eating birds living in boreal (northern coniferous) forests sometimes get pushed south," he said. "They're really exotic birds for around here."
At Meadowbrook Park, you can spot beavers at sunrise, he adds.
Farther from here, southern Illinois' Ferne Clyffe State Park  is a favorite of Post's.
"During winter in southern Illinois, the weather is always capricious — one day warm, one day wet, the next, freezing cold," she wrote. "At Ferne Clyffe, water drips off the sandstone cliffs, and if the temperature is below freezing, a forest of icicles forms. The decorations look like lace curtains hanging in an old Victorian mansion."
At Cache River State Natural Area  in the Heron Pond Nature Preserve, Post has seen "an embossed frog quick-frozen in the duckweed, large marauding flocks of blackbirds taking off and landing in the woods, or fleeting glimpses of both winter wrens and brown creepers. The round trip from the parking lot to the boardwalk is 1.5 miles."