Geocaching, The Susquehanna, And The 1996 Flood

I was surfing around for some geocaching links today -- I've never done it, but I'm thinking I might give it a try this summer. After all, it involves walking around outside, and gadgets. What more could you ask for? For those who are unfamiliar with it, geocaching is an activity where you use a GPS receiver to try to track down a "treasure" which has been hidden somewhere. It's like orienteering crossed with a scavenger hunt and it looks like a fun way to spend a weekend afternoon.

Anyway, when I went looking for geocaches in the Harrisburg area, I found one cache that appears to be hidden in the Sunken Garden, which I walk to almost every day either with Zo or the dogs. It includes a bunch of photos of Riverfront Park during the 1996 flood, which saw the Susquehanna River rise 15 feet in 14 hours and eventually tear the Walnut Street Bridge off its moorings and smash it into the Market Street Bridge. This one is my favorite:



The river has been rising and falling over the last few weeks, but of course it hasn't gotten close to that height. The first warm spell took it up over the walkway along the river, and when it receded, it left giant chunks of dirty ice along the walkway. It went back down, and then after the next rain, it was back up over the walkway, leaving a giant bathtub ring of mud along the side of the river. It was back down for a few days but as of this weekend it was up again, due to Thursday's rains. Here's the graph of river height from the USGS website:



(That's measured at the Market Street Bridge, by the way. And kudos to Mapquest for being the only mapping site that allows you to easily map by latitude and longitude.)

Have any of you geocached before? Is it fun? I figure I could take Zo along on the hunt for some of the easier treasures, especially ones like this which are walking distance from my house.