Sunday Bikedays:
This is the last weekend to participate in the 40th season of the Alcatel-Lucent Sunday Bikedays. Hop on your bike or grab your in-line skates and hit the parkways in the heart of the Capital Region and Gatineau Park, which are closed to motor vehicles every Sunday morning through Labour Day weekend. Closed from 9 a.m. to 1 p.m. are the Ottawa River Parkway, Colonel-By Drive and Rockcliffe Parkway. The Gatineau, Champlain and Fortune Parkways are closed to motorized traffic from 6 a.m. to 11 a.m.

Ottawa Serbian Festival: The 5th Annual Ottawa Serbian Festival showcases the rich history of the Balkan culture, which includes savouring delicious Serbian foods, partaking in traditional Serbian and other cultures’ folk dances, and enjoying both modern and traditional Serbian music. Saturday to Monday, St. Stefan’s Serbian Orthodox Church, 3662 Albion Rd.

Benefit Ride to End Breast Cancer: A non-profit group, the Eastern Ontario (Ottawa) Harley Owners Group, is partnering with the Ottawa Regional Cancer Foundation to host the Benefit Ride to End Breast Cancer. This event is open to all motorcycle enthusiasts. There is a poker run and some great prizes, and all for a great cause. Saturday, 9 a.m., Harley-Davidson of Ottawa, 505 Industrial Ave.

Mackenzie King Estate summer season opening: Visitors to this 231-hectare estate can share William Lyon Mackenzie King’s love of horticulture and landscaping while admiring the romantic Victorian gardens, the picturesque ruins and the Waterfall Trail. Stroll through the gardens, photograph the collection of ruins and enjoy a meal. This weekend, check out the Estate in Bloom. Saturday, Mackenzie King Estate in Gatineau Park

The Canadian Marathon, Half-Marathon, 8 km and 3 km Fun Runs and Iron 226 Triathlon and Duathlon: More than 1,300 people are expected at this all-day, Somersault-run event, which features the Iron 226 Triathlon and Duathlon and 3 km and 8 km races in the morning and the marathon, marathon relay, and half-marathon happening in the early evening. There’s still time to register — and part of the proceeds go towards Carefor and Kidsport Ottawa. Saturday, Terry Fox Athletic Facility, Mooney’s Bay

The Ottawa Inline Festival: Now a part of the National Roller Cup Series, the Ottawa Inline Festival features events for all abilities. These include a Triple Crown race, a 10 km event, 5 km fun race for the kids and a pro division for the marathon. All events start at the festival village at Blair Road and Massey Lane. Sunday, various times starting at 1 p.m., Rockcliffe Parkway.