During our cruise around the eastern coast of South America, I took pictures of many things.
However, this post is about a particular septet of photographs. Here, have a look. There will be a quiz later.
The seven photos above all contain objects that share a common theme. The first part of your challenge is to discover what those objects are and what they have in common. Once you discover that commonality, your next step is to figure out what are some other objects I could have included that fit the common theme.