I once used a quotation of George Santayana's against an opponent in a high school debate: "Those who cannot remember the past are condemned to repeat it." I was reminded of that today, as apparently my own memory has started to go!
Twice now, I've arrived at the coordinates for a geocache to find an open expanse with no likely hiding spots in sight. Both of those times, the cache in question was located UNDER the path upon which I was standing: once in a pedestrian tunnel and once in a drainpipe. As you might expect (or hope!) I was a lot quicker on the uptake the second time than the first. Latitude and longitude pinpoint a location on the Earth (the proverbial X marking the spot) but tell you nothing about how far above or below the X you should be looking.
I had to go to Costco today, so I took the opportunity to try a second time for a cache that defeated me entirely on my last Costco trip. The posted coordinates brought me to the corner of a parking garage in a shopping mall, and both times I spent more than an hour fruitlessly poking around the wire-fenced enclosure and handrails near the stairwell at that corner, just hoping that nobody would see me loitering suspiciously and call Paul Blart! By the end of my explorations today, I'd had it with dodging pedestrians--I gave up in disgust and fired off an email to a geocacher friend who had previously found it asking for a hint, then took off for Costco.
By the time I arrived, he'd responded. "Did you go up the stairs??"
Sure enough, when I stopped back for the third time on my way home, it took me all of 30 seconds to find the cache, which was suspended from fishing line off the edge of the top deck of the parking garage, directly above the fenced enclosure I'd previously been examining so unsuccessfully.
So now I have officially been thrown by caches located both below and above ground level. The real test will be whether I remember to look up the next time I'm stymied!