This is the twenty-seventh instalment of the Fortnightly Topic Challenge described here, with topics suggested and voted on here. This fortnight's topic is treasure-hunt (suggested by user14478), and will span from the the 20th of February to the 5th of March. During this period, we will compile the list of questions with this tag and post it as an answer to this question.
In the meantime, please go and propose and vote on future challenges!
Everyone have fun, and happy puzzling!
Link to other Fortnightly Topic Challenges.