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The Lock

A cache by fidian Send Message to Owner Message this owner
Hidden : 3/3/2006
4.5 out of 5
2.5 out of 5

Size: Size: regular (regular)

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Geocache Description:

If this is the lock, where is the key?

Not At Above Coordinates!

The coordinates listed above are for the park entrance, not the actual cache location!

This cache is located in a nice park. The tough part is finding it. In order to open The Lock, you need to first locate The Key, which is a padlock travel bug (TBJVJJ). Once you have The Key, you need to figure out the combination to the lock without physically damaging the lock and look up the serial number on the back.

With the combination in hand, you need to look up the last four digits of the serial number on the table below to get the formula that will result in a number. Digits from this number will be used to find the cache.

Cache is loaded up with locks and other goodies. The lucky GeoFishing4Caches got the amazing First To Find prize, Microsoft Streets & Trips 2005.

About The Park

The St. Croix Bluffs Regional Park is a Washington County park. It has 579 acres of fields, grasslands, wooded areas, 3,800 feet of shoreline on the St. Croix river, and some nice cliffs. There are picnic shelters, camping areas, trails, water fountains, a "conference cottage," and much more.

The park does charge $5 for a day pass, or you can get in free if you have a Washington, Anoka, or Carver county park pass. Depending on how this cache is hidden, it might just be a park-and-grab, or you may need to get a pass and spend a while hiking.

This park needs more caches. If you want to hide a cache in this park, go find a location for yours and let me know the coordinates. I will make sure that my cache is far enough away from yours so that you can get yours approved.

How To Find The Cache

  1. Find The Key.
  2. Write down the last 4 numbers of the serial number on the back.
  3. Determine the combination of The Key.
  4. The combination will give you AB-CD-EF. If the combination has a single-digit number, such as 11-5-8, you will put in zeros as in 11-05-08.
  5. Look up the serial number on the table below.
  6. Enter in the numbers, replacing A through F appropriately.
  7. The results will give you two numbers.
  8. Divide both results by 1000, then plug them in here:
    N: 44°
    W: 092° 4y.yyy
  9. Please re-hide The Key when you are done so others have a fair chance of finding the cache.
Last 4 Of
0080 X: (271 * CA) + FFDE + 888
Y: (FED * 2A) - BD0 - 19
X: F5E + (A * B) + 75D8 - C4
Y: (ED * C) + 9B0 + ((F / 2) * 16A0)
3902 X: (8C / F) + (B * 5) + (74 * AD) + 62E0
Y: 10C3B + 926 - FADE
X: F3DA - (14 * BC) - (26 * E) - 1
Y: 7CB4 + (EFA2 / 2) - (D0 * 2)
X: 3EB * (C + (AF)) + D + 91
Y: 8EBF - (AD * 43) + C63
X: (D * E * 6) - A7B + 82FC - 54
Y: (E * DA) + ((B08 - F) * 7) + 624C
5631 X: 8201 + ACE - DEB + 3F2
Y: (CE * A * 232) + (BF * 12D) + 867 - 5309
8439 X: (A + C) * 2705 + BF7 - (E * D)
Y: 1B8C + (E * 2F92) + (A * D)

If you found a lock with the serial marked as "invalid", read about why it is invalid on this page.


You found The Key and figured out the combination. Let's pretend that the serial number is X370002486E and the combination is 31-4-28, which should be written down as 31-04-28. You look up 486E on the table above and find out the two formulas. X = 8343 - (14 * 10) - (26 * 2) - 1 = 8150. Y = 7014 + (2832 / 2) - (40 * 2) = 8350.

With those two numbers, we now plug them into our location by first dividing them by 1000. 8150 / 1000 = 8.150 and 8350 / 1000 = 8.350. Inserting them into the coordinates gives us N: 44° 48.150 and W: 092° 48.350. Remember, this is just an example and the cache is not actually hidden at this particular location.

Additional Information

This cache was inspired by Your 100th Anniversary and the time that I found it. Even though you now don't need the combination emailed to you, DO NOT OPEN THAT CACHE unless you have 100 finds. It is stated very clearly that you can not log the find unless your profile says you have 100 finds.

I hope that you now think twice before using a combination lock when protecting very valuable things. MasterLock's own web page calls the lock a "theft deterrent," not claiming that the lock makes things 100% secure.

The "example" combinations shown here are invalid. It might be good for practice if you could figure out why they are invalid. Each combination is invalid for a different reason.

WARNING: Any logs that could be construed as hints will be deleted immediately. If the hint is blatant enough or if any part of the combination is revealed, countermeasures will be employed. The lock could be replaced, the formulas may be reworked, the cache might be relocated.

Minnesota Geocaching Association

Additional Hints (No hints available.)



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