Choose an image – it could be something you’ve found online or one you have taken. In a comment, add your image and write alt text that will allow someone to imagine the image without seeing it. The way you write the alt text may differ depending on the context of the image.
Example
Cat posing in front of a Roman wall, with city buildings in the background.
Alternatively:
Wall from the 1st century Roman theatre of Philippopolis in the city center of Plovdiv.