Great Outdoors Week is mostly a marketing campaign, but it's filled with substance -- mud, boulders, rushing water, wildflowers, feathers.

Those are some of the basic elements you can get your hands and feet on during this annual celebration of outdoor recreation. The supersized "week" -- to be proclaimed this morning by Pittsburgh City Council -- starts Friday and stretches to May 22, tying together nine days of dozens of big and small outdoor events across Western Pennsylvania. It climaxes with the free Venture Outdoors Festival on the North Shore on Saturday, May 21.

Venture Outdoors, the group that publicizes the activities and organizes many of them, again is working with Sustainable Pittsburgh on Great Outdoors Week, which aims to raise the profile of the region's ample natural assets.

The promotion takes on a healthy bent this year, as it joins with the Working Hearts May Community Challenge. All month, the Jewish Healthcare Foundation is challenging people to get out and do as many activities as possible (see www.workinghearts.org or 412-594-2583).

Other big events are back
:

Pedal Pittsburgh, a bike ride over five different neighborhood routes on Sunday (www.pedalpittsburgh.org or 412-232-3545).

Three Rivers Rowing Association's learn-to-row and learn-to-paddle events at its Millvale training facility Saturday and next Wednesday (www. threeriversrowing.org or 412-231-8772).

Bike Pittsburgh's "Park 'N Pedal" commuter rides to Downtown next week (www.bike-pgh.org or 412-576-5982).

But Great Outdoors Week also is packed with many smaller events, such as Saturday's jam-packed International Migratory Bird Day Hikes at two not-far-away Audubon Society of Western Pennsylvania reserves, Beechwood Farms and Todd Sanctuary. Audubon's Trisha Harger thinks the promotion is a great way to showcase the variety of places to play outside. "I hope it inspires people to appreciate just what we have here."

Here's a sampling of activities you can try, day by day:

Friday

Explore "Bats and Bullfrogs" habitat with a Three Rivers Habitat Partnership biologist at the 300-acre Bayer wildlife reserve beside Settler's Cabin Park.

Saturday

Take a Botanical Society Field Trip at Raccoon Creek State Park. Or sojourn down Chartiers Creek with the Scott Conservancy. Or do the Pittsburgh Garden Swap at the Frick Environmental Center. Or ...

Sunday

Navigate Indiana County with the Western Pennsylvania Orienteering Club. Visit Harrison Hills Park in the Buffalo Creek Valley Important Bird Area with the Audubon Society.

Next Week

Monday

Learn to sea kayak on the Allegheny River with Venture Outdoors (starts from Kayak Pittsburgh, a rental spot beneath the Clemente Bridge).

Tuesday

Practice yoga in Boyce Mayview Park. Take a river venture, on a 44-foot houseboat, from Rockwall Harbor Marina in Rochester, Beaver County.

Wednesday

In-line skate in the East End with Three Rivers In-line Skate Club. Hook up with the Downtown TriAnglers for weekly lunchtime fishing at the Point. Take a Pittsburgh History & Landmarks Bridges & More walking tour Downtown.

Thursday

Paddle and play with various whitewater boats from Wind & Water Boatworks on Slippery Rock Creek near McConnells Mill State Park.

Friday

Savor a Wine & Cheese Hike in South Park (if you're at least 21). Or try out more boats at Paddle Fest on Moraine State Park's Lake Arthur.

Saturday

Canoe the upper Allegheny River with the Allegheny Outdoor Club. Bike Around the Bay at Erie. Chip in at the Healcrest Urban Community Garden. Be in or watch the Pittsburgh Urban Race Extreme.

You also could hook up with any number of other outdoorsy groups, such as Outdoor Adventure Learning, which runs a full schedule of its own outings (www.outsideadventures.org or 412-968-0310).

Or just go to one of the region's many parks or rivers.

For more information and schedules of Great Outdoors Week activities, go to www.VentureOutdoors.org, www.workinghearts.org (click on "May Community Challenge") and www.GreatOutdoorsWeek.org.