The Treasure of Columbia Lake

You've always wanted to be an adventurer, to explore a colossal cave, slay dragons, be eaten by a Grue... ok, maybe not that last one... but you never thought you'd get the chance, seeing as you live in New York in the 2020s, and not some distant or magical realm. And then you saw an ad in the New York Times, yes, a paper newspaper, how old-fashioned of you, to go on an adventure of a lifetime, to find a great treasure in Columbia Lake, Cherry Hill, New Jersey. You, of course, answered the call, not only because it has always been your calling, but because you are desparate, and only have $20 to your name... long story.