A cat sitting on a concrete fence looks down at the camera. Original public domain image from Wikimedia Commons https://www.rawpixel.com/image/3288603/free-photo-image-abyssinian-adorable-animalFree Image from public domain licenseUrban sidewalk by the fences at Santa Barbara. Original public domain image from Wikimedia Commons https://www.rawpixel.com/image/3290586/free-photo-image-arbour-architecture-banisterFree Image from public domain licenseU.S. Airmen from the South Carolina Air National Guard’s 169th Civil Engineer Squadron at McEntire Joint National Guard… https://www.rawpixel.com/image/4043282/photo-image-people-nature-wallFree Image from public domain licenseIndustrial building with connecting steel walkways https://www.rawpixel.com/image/534673/free-photo-image-factory-architectural-architectureView licenseShot from under a bridge https://www.rawpixel.com/image/534698/free-photo-image-gates-architecture-beamsView licenseConcrete wall, one half mile long, Detroit, Michigan. This wall was erected in August 1941 to separate the section from a… https://www.rawpixel.com/image/12285087/photo-image-cloud-plant-grassFree Image from public domain license