Free historic sites in Ottawa
Canadian Museum of Nature
Free outside, paid inside
Photo: Michel Rathwell from Cornwall, Canada, CC BY 2.0 Sparks Street
Free, alwaysNational War Memorial
Free, always
Photo: Hayden Soloviev, CC BY 4.0 Notre-Dame Cathedral Basilica
Free, always
Photo: Harleyd613, CC BY-SA 4.0