This is no subtle ploy. “Put on your gear, prepare your heart;” this is a call to action!

The gear here is no more than comfortable shoes to walk in. You can bring other things if you have them, perhaps a bicycle, fishing rod or canoe.

Within the semicircular rim from West Rock around to Sleeping Giant and back toward the water at East Rock, some prehistoric movement created for us much to experience.

Almost 200 million years ago, the earth’s center discharged a parapet of molten slag into the silty sediment around the spot where New Haven would be built. Subsequent wet seasons and winters have eroded enough of the soft red sandstone to reveal sheer ramparts of hardened trap rock from our planet’s core — these are East and West rocks. Rising global temperatures flooded an inland lake, pushing what we know as the Long Island Sound north toward the feet of their peaks. Your schoolhouse was formed.

Do not be intimidated by the superhuman strength of such primal actors. You come from noble stock.

Your forbearer Clarence King — founder of the U.S. Geological Survey and Yale-Sheffield student — wrestled with the implications of enlisting in the Northern army while hiking the hills around New Haven and captaining a Yale boat on the Sound.

East Rock was for him a springboard to the climbing of Mount Whitney and the famous mountaineering narrative it spawned, his “Mountaineering in the Sierra Nevada.”

Aldo Leopold, another Sheffield man and the “father of wildlife ecology,” spent countless days exploring the environs of New Haven early in our century, percolating early notions that would culminate in his “land ethic.”

It was the colorful New Haven autumn that, at least in part, spurred his ode to another scene, “A Sand County Almanac,” forever changing the way Americans think about their landscape.

Nature is inviting you, too, to learn from this small slice of her scheme. She has given us, this year, a few extra weeks of temperate weather. I checked the forecast; I hope it will hold long enough for you to understand what I mean. The leaves of crimson and bronze are holding on the branch for us to see. The lapping shore break of the Sound is still warm enough to take off your shoes and wade in.

There is a family of swans on the Mill River who will come close if you make no sudden movements. If you take the short walk down Whitney Avenue to the Eli Whitney Water Museum and its falls, you can follow footpaths downstream and perhaps spot them through the foliage.

Then take the 285-foot hike up East Rock itself by the “Giant Steps” route. At the top you’ll find a stunning view of the campus you call home.

Instead, you might catch the G bus from downtown (it leaves about once an hour on the weekend from the corner of Chapel and Church streets). After a quick ride, you’ll find men with surf-casters on jetties and a fishing pier at Lighthouse Point Park. They’ll tell you their bottom rigs are begging for stripers, but most likely, all you’ll encounter are a few sea robins in a bucket. Locals say these odd bottom-feeders are good eating, too, although it’s hard to believe anyone would put them on a plate.

At Lighthouse Point, there is a long sandy beach. You can bring a towel to lie on, or not; that is not essential gear. Take off your shoes and wade into the Sound, you can even swim if you want — it is not that cold yet.

If it’s the currents you want to explore, though, you might be better off taking the B instead of the G. Head off to West Rock, where this weekend’s “Canoe New Haven” event will take place on the West River. An oarsman from the New Haven Department of Parks, Recreation and Trees will skillfully usher you upstream while you take in the colors.

Autumn has held out a little longer this year for us. But she cannot hold much longer — “and swift as a hawk from snowy Olympos’ height” — winter will envelope it all.

Don’t miss your chance.