Six rabbit holes worth falling into. Open one and follow the links out.
A board starts with one article. These six start with an article plus the four people usually click through to next, already placed and connected, so there is something to read and somewhere to go from the first second.
Or start from anything
The starters are seeds. Press S on a board and search for whatever you were actually curious about. Any article in any of Wikipedia's language editions works the same way.