The following rules apply to each puzzle:
1. The letters of each station name must appear, in sequence, at some point during the text. They may be separated by spaces, punctuation marks, the ends of sentences or ends of paragraphs, but not by other letters. Spaces or punctuation marks in the name of the station do not have to be included in the text.
2. Each station name must occur once and once only. But if two stations share the same name, then the name should appear twice.
3. No station name may be contained within another station name. So for example if there were two stations called "Dogsbury" and "South Dogsbury", they would occur separately within the text. Overlapping station names are not permitted either: "South Dogsbury" and "Dogsbury Park" would have to occur separately.
4. If a station name consists of a single word, that word must be either split between two or more other words, or contained within a longer word. So for instance the station name "Bank" could appear as "let's BAN Kerry from this place", or "he decided to file for BANKruptcy", but not as "he made a visit to the BANK". This restriction does not apply to station names of two words or more.
5. No station name may be used as a whole to refer directly to the station or location in question. However it is acceptable for part of the name to do so. For example:
"He travelled to BIRMINGHAM NEW STREET" - unacceptable
"He travelled to BIRMINGHAM. NEW STREETlights had been installed" - acceptable
6. Any part of a station name that appears in brackets should be ignored. Likewise any part of the name that begins with "for" (as in "Cutty Sark for Maritime Greenwich").
Highlighting convention Edit
In the solution to each puzzle, and while the puzzles are being constructed, the normal convention is to write the letters of each station in capital letters, but otherwise to write the text as normal.
There is one exception to this: if a word in the text is a proper name, beginning with a capital letter, and the second letter of the word is the beginning of a station, then the first letter of the name should be written in lower-case.
Example: the station name "Ayr" is concealed within the proper name "Ray Reynolds". This is written in the solution as "rAY Reynolds" rather than "RAY Reynolds" (which would suggest "Rayr" as the station name).