These are my photos from parks I have visited (I didn't take them, they are all from Wikimedia Commons).
This shows you how to make a simple image gallery using articles in com_content.
In each article put a thumbnail image before a "readmore" and the full size image after it. Set the article to Show Intro Text: Hide.
Lorem ipsum dolor sit amet, consectetur adipiscing elit. Aenean vitae viverra lorem. Donec lacus mauris, suscipit at tortor eget, posuere fermentum velit. Cras placerat blandit lacus eu maximus. Integer id vulputate leo. Nunc ut elementum urna. Maecenas ut consequat lacus. Aenean non nulla ex. Sed sed tellus id felis semper faucibus interdum eget quam.
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