$2. 10 a.m.-3 p.m. Cape Florida Lighthouse, Bill Baggs Cape Florida State Park, 1200 S Crandon Blvd., Key Biscayne. Details: (305) 361-5811.
Stiltsville Key Biscayne Boat Tour. See the extraordinary neighborhood in the middle of Biscayne Bay, restored Cape Florida Lighthouse and Villa Vizcaya. Tour sails from Bayside on the Heritage of Miami II. $25; $20 for members. Noon-4 p.m. Meet at Bayside Marketplace, 401 Biscayne Blvd. Details: (305) 358-9572.
BOCA CHITA KEY WALK
A former hideaway for the rich and famous in the early 1900s. Boat fees are $19.95 for adults, $17.95 for seniors and $12.95 for under 12. Meet at the lighthouse at 2:15 p.m. or call to arrange boat transportation. Details: (305) 230-1100.
Miami Beach Millionaire's Row Bike Tour by Paul George for the Historical Museum of Southern Florida. $15; $10 for members. 10 a.m.-12 p.m. Meets at Citibank on 41st Street and Sheridan Avenue. Details: (305) 375-1621.
With book signing by Becky Roper Matkov, editor, Miami's Historic Neighborhoods. 11 a.m.-1 p.m. Gardner's Farmer's Market, Southwest 124th Street and US 1, Pinecrest. Details: (305) 358-9572.
Celebrate the restoration of Althea Merrick's grotto, complete with waterfalls, pools and lush landscaping. Free but reservations required. 3-5 p.m. Coral Gables Merrick House. Details: Carol McGeehan, (305) 460-5361.
Coconut Grove Twilight Walking Tour with Paul George. Explore the sites of early homesteader settlements, Peacock Inn, Barnacle, Millionaire's Row. $15; $10 for members. 5-7 p.m. Meets at Miami City Hall, 3500 Pan American Drive, Coconut Grove. Details: (305) 375-1621 or historical-museum.org.
MIAMI RIVER DAY
Sixth annual. See special events. 12-6 p.m. Jose Marti Park, 351 SW 4th St. Details: (305) 579-6958.
Art Deco Bike & Rollerblade Tours by the Miami Design Preservation League. $15: add $15 for bike or blade rental. 10:30 a.m. 1001 Ocean Drive at the Art Deco Welcome Center, Miami Beach. Details: (305) 531-3484.
The Commodore's birthday is celebrated on the grounds of the Barnacle. 4:30-6:30 p.m. 3485 Main Hwy., Coconut Grove. Details: (305) 448-9445.
Charles Deering Estate Plant Walk, organized by the Tropical Audubon Society. Sturdy shoes required. Call for reservation & time. Space limited. Details: (305) 666-5111.