Nature-expert guided walks in Tenney Park along Lake Mendota and the Yahara River Parkway bike path through the Madison Isthmus are free, family-friendly and held the first Saturday of each month, from 2:30-4pm. The walk begins at the Tenney Beach parking lot, 1330 Sherman Avenue. No registration is required. No pets are allowed. Co-sponsored by Madison FUN Friends of Urban Nature, Madison Parks, Madison Audubon Society , Tenney-Lapham Neighborhood Association  and Friends of the Yahara River Parkway .