Twofer - Audubon Park Traditional Cache

This series will provide you with a dual return if you choose to make just a little bit of extra effort. Each cache in this series is located very close to a benchmark. Not only can you get the smiley, you can add a benchmark to your finds list.

BENCHMARKS

You can read more about benchmarks in greater detail at geocaching.com but here is some basic information for those of you not familiar with benchmarks.

What is a benchmark? A benchmark is a point whose position is known to a high degree of accuracy and is normally marked in some way. The marker is often a metal disk made for this purpose, but it can also be a church spire, a radio tower, a mark chiseled into stone, or a metal rod driven into the ground. Benchmarks can be found at various locations all over the United States. They are used by land surveyors, builders and engineers, map makers, and other professionals. Benchmarks come from the National Geodetic Survey (NGS), a federal agency within the Department of Commerce. The NGS database contains all sorts of information about these benchmarks. In the NGS database, each geodetic control marker has a Permanent IDentifier, known as a PID and an associated datasheet of information about it.

Why search for benchmarks? The interesting thing about benchmarks is that a majority of them are located in plain sight (though largely ignored by the general public). Searching out these locations and documenting them allows others to share pictures of the various areas where they are placed. There's a certain excitement to be the first to find and document a control point, as well as seeing what others have found through uploaded photos. Some of these points haven't been visited and documented in a very long time, so you may also be rediscovering long neglected objects of American history as well!

How does someone find a benchmark?

• Choose some benchmarks to search for and get their datasheets. Datasheets contain the coordinates and a description of where to find the benchmark. If I am planning on hunting a cache, I will often click the "Nearest Benchmarks" link on the cache page to see if there are any benchmarks close to the cache site.You can also go to the benchmarks homepage and search by zip code. The easiest to find are the ones that have been found by someone else using Geocaching.com and have uploaded pictures showing the mark's location.
  
  
• Do not set out with coordinates only; you must have the verbal to-reach description in the datasheet with you when you go. The coordinates are often inaccurate. Using the written description can help you locate the benchmark more quickly. Later, if you do find that the coordinates were incorrect, take a mark of your own and post it to the benchmark page for future hunters to use.
  
  
• The hunting process: When you arrive at the area of a benchmark's location but before you get out of your car, read the datasheet carefully. The first thing to note is whether the mark is location-adjusted or location-scaled. Next, read all the benchmark's recovery notes from the most recent to the oldest. In each recovery note, the most important item of information is the distance and direction of the landmark that is the the shortest distance from the station. Start with the closest landmark of all the recovery notes and see if you can find it. The most accurate instrument you have is your tape measure, not your GPSr, so use the tape measure first. If the mark can't easily be found, continue with the next closest landmark and measure from it to an intersection area with the distance you measured from the first landmark. If you don't see the mark yet, probe the ground in the area with a probe, (benchmarks often get buried) searching for the disk plus its monumentation. If you haven't yet found the mark, read older recovery notes again to try to get more information, since many recovery reports don't bother repeating older recovery information that's still good.

THIS TWOFER

The Cache - Parking can be an issue. DO NOT PARK ON THE STREET THAT RUNS BESIDE THE CACHE - IT IS A SUPER BUSY STREET!!! Park on Cherry at your own risk. I suggest you park at the nearby Botanical Gardens or at the start of the Audubon Park walking track. Now, to get the smiley, look for a silver bison tube at the posted coordinates. Use the hint if needed. Please replace as found after signing the log. Hide it well. Enjoy!

The Benchmarks - There are two benchmarks very close to this cache so this is really a three-fer.

FE2199 - You can view the datasheet using that link but here is some information. The benchmark is a reference mark disk. The posted coordinates are N 35° 06.450 W 089° 55.133 but the mark I took is N 35° 06.440 W 089° 55.158. The disk is set in the sidewalk very close to a telephone pole. Taking a picture of the disk is not required to log the benchmark but post them if you have them. You may also take pictures of the surrounding area if you see anything interesting or helpful. To log the find, go to the geocaching.com page for the benchmark and click " Log this benchmark". From there it is a similar procedure to logging a cache.

     

FE2197 - You can view the datasheet using that link but here is some information. The benchmark is a triangulation station disk near a large maple tree. The posted coordinates are N 35° 06.440 W 089° 55.135 but the mark I took is N 35° 06.439 W 089° 55.139. The disk is set in concrete but the disk and concrete are in the grass so they often get covered with dirt or mud. Finding this one may require a little digging. Taking a picture of the disk is not required to log the benchmark but if you happen to get a good, non-muddy picture, please do upload it. You may also take pictures of the surrounding area if you see anything interesting. To log the find, go to the geocaching.com page for the benchmark and click " Log this benchmark". From there it is a similar procedure to logging a cache.

    

BONUS

I went ahead and created a waymark for each of these benchmarks, too - WM3HZT and WM3HZP. If you do waymarking, make sure to log it. For that you WILL need a picture to upload.