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Details for Benchmark: AI4425

N 38° 53.333 W 077° 02.100 (NAD 83)

Altitude: 39.58

Coordinates may not be exact. Altitude is ADJUSTED and location is SCALED. (more info)

Location:
In DISTRICT OF COLUMBIA county, DC View Original Datasheet
Designation:
W M BASE NE
Marker Type:
NGS Benchmark
Setting:
setting not listed - see description
Stability:
May hold, but of type commonly subject to surface motion.

Must Read!

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With family visiting for a couple weeks, we have to show them some of the local sights. This was a great opportunity to tour the DC mall while secretly doing a little geocaching (and benchmarking) on the side. Easily found and in great condition.

[Photos:]
photoAI4425

Found in good shape while exploring Washington DC with TaGeez

Found it on an unseasonably warm evening in March on a trip to D.C. with the girlfriend. She had an all week conference, and I just geocached and hunted marks!

In DC for a conference and mapped out an ambitious agenda for finding virtual, earth, multis, puzzles and regular caches, as well as some bench marks!
Walked all around the monument!
TFTC< ponil

found while doing the area virtual caches

At the monument I found this benchmark as well. Thanks for showing. :)

[Photos:]
photo12

Located this BM before going up to the top

[Photos:]
photoAI4425
NE corner washington monument

Found while walking the mall with friends from the UK.

[Photos:]
photoNE

Got the cover.

[Photos:]
photoai4425

Observed while visiting the Washington Monument.

[Photos:]
photoAI4425 Benchmark
located in Washington, D.C.
photoAI4425 Benchmark Area
located in Washington, D.C.

Great find for another Washington benchmark.

Discovered while waiting for our tour inside

Logging some benchmarks after a long time on my list. Sorry for the late logging.

Most of the logs below are discoveries of "WM CASEY NE (AJ1996)" as described by seventhings in 2003

The current NGS datasheet for this mark (W M BASE NE - AI4425) lists a 'not found' - see recovery note below: http://www.ngs.noaa.gov/cgi-bin/ds_mark.prl?PidBox=AI4425

AI4425 STATION RECOVERY (2012)
AI4425
AI4425'RECOVERY NOTE BY NATIONAL GEODETIC SURVEY 2012 (DRD)
AI4425'NOT RECOVERED.
AI4425'
AI4425'NOTE-A NEW PROMENADE WAS LAYED AROUND THE MONUMENT.

Found while on vacation

Found wandering the monuments today.

Found while caching.

Filling in some missing Benchmarks that I have discovered over the years.

Found this Benchmark while Geocaching in the area today. The cover is secured and cannot be opened to get an actual pic of the BM.

[Photos:]
photoBM AI4425

Recovered on Sunday morning. The cover no longer has "W M CASEY" stamped on it, but does appear in the same location. It also has a Torx nut holding the cover shut.

[Photos:]
photoAccess cover to old W M CASEY mark in NE corner
photoLocation of AI4425

another nice one :_

Took a short jog around the monument to find this one. Nice little cover, though I think the designation engraving has been worn off a bit.

[Photos:]
photoThe cover
I'm pretty sure this is the right one... they all look the same

Found it

another quick find!

[Photos:]
photoDSC02104

Found this benchmark whilst doing a rapid tourist trip around Washington. Nice easy find...photo to come.

[Photos:]
photoAI4425

A walk around Washington Monument to find all the BMs.

[Photos:]
photoAI4425

[white][/white]

Found during lunch-time walk around the monument.

[Photos:]
photoAI4425 Benchmark
photoVicinity of GZ AI4425.
Cover over benchmark is just out of picture - Closer to photographer than what is visible in picture. Cover is just off the NE corner of monument.

Easy find

[Photos:]
photoAI4425

In DC for the week to attend a Geographic Conference, got out of class early so I decided to head to the mall for a few markers.
Got there at 4:30, National Christmas Tree lighting at 5:00 PM so I could not get a few I wanted.

[Photos:]
photoAI4425

Found while in D.C. with the family geocaching and vacationing!

Found in good condition.

found while caching and on vacation

Found the cap but there were a few too many people around to open.

Found this one. Park police explained the pvc tube that connected current level to the original placement under the cover.

had some time before a tour of the red cross building

[Photos:]
photone

Found this while visiting the monument.

This one appears to still be covered - found WM CASEY NE (AJ1996) as described by seventhings in 2003.

The AJ1996 datasheet mentions in 2000 the promenade placed around the monument which would make WM BASE NE inaccessible - see below:

DESCRIBED BY NATIONAL GEODETIC SURVEY 2000 (DBC)

'IN WASHINGTON D.C. AT THE WASHINGTON MONUMENT. THE MARK IS 1.6 FEET (0.5 M) NORTHEAST OF NORTHEAST CORNER OF WASHINGTON MONUMENT 28.7 FEET (8.7 M) NORTH OF WM CASEY EAST, 4.1 FEET (1.2 M) EAST-NORTHEAST OF BENCH MARK A 8. A PROMENADE WAS LAYED AROUND THE MONUMENT AND NGS LOGO CAP WITH A 1 FOOT (0.3 M) LONG PVC PIPE TO PROTECT BENCH MARK THE LOGO CAP IS FLUSH WITH THE PROMENADE AND BENCH MARK IS 18 INCHES BELOW CAP.

AJ1996 is listed at waymarking.com - http://www.waymarking.com/waymarks/WM506

[Photos:]
photoWM CASEY NE (AJ1996) - lid
photoWM CASEY NE (AJ1996) - area looking ESE

Found this one while walking around the mall on a surprisingly warn evening with some friends.

Found all the base Benchmarks, but not sure which ones are which now. I think I've got the in the right order, but...

[Photos:]
photoIt's dark, but it's down there!
No screws held the covers closed when I was here in summer of 2008, so you could open the covers and see the stations. (Even if they didn't photograph well!)

Found with my family while strolling around the Washington Monument.
King Hubi

[Photos:]
photoAI4425 - W M BASE NE [closeup]

Found on our lap around the Mall today

Found this by accident!

Easy to find.

Found on a virtual / benchmark run in the mall.

:}

Found while in touring the area today!

[Photos:]
photoAI4425

Saw during tour of the Washington Monument. Opened cover, nothing to see inside.

[Photos:]
photoAI4425
AI4425

Found this one while on vacation
elawsan

Found as described and recovered in good condition.

[Photos:]
photoclose up AI4425 - Washington DC

Stringfam then found the third. Hmm the pattern is forming will check the last corner. No screws on lid and the hole is full of mud.

We found this one and three others in the vicinity while in DC.

[Photos:]
photoAI4425

There is dirt in the hole, bring a flashlight to see down in.

Spotted this one today after ascending and descending the monument.

Ran over at lunch time to grab this BM.

Was at the monument this am and found the covers. Checked with onsite security if I could open the covers to photgraph the marks, but was denied permission. All I can say, is the covers are there and in good condition.

Found this one while visiting the Monument.

Got it.

Visiting WM

Yet another covered Benchmark at the Washington Monument.

[Photos:]
photoAI4425

Found with Charlie.

All the base Monuments and the 2 Stainless pins.I also have the Peace Medal on all them.

[Photos:]
photoWMNE
Opened acess cover the rod is down there.

Could not find this mark as it lies seven inches below the concrete surface. Unlikely that anyone else has found it either - no evidence of any recent disturbance in the concrete pad around the monument. However, I found W M CASEY NE, PID = AJ1996 - in the NGS database but not in the Geocaching database. A photo of W M CASEY NE is attached.
Revisited 12/16/05: WM Base NE is still not visible. WM CASEY NE is a Waymark at:
http://www.waymarking.com/waymarks/WM506

[This entry was edited by seventhings on Monday, September 24, 2007 at 11:20:29 AM.]

[Photos:]
photoW M CASEY NE, not W M BASE NE
PID = AJ1996.

Found this benchmark while visiting the Washington Monument while in DC on a business trip.

I thought I had this monument also, until I noticed that the monument found near this location is actually: NGS PID AJ1996; WM Casey NE. WM Base NE is supposed to be 7 inches below the surface, I saw no sign of that.

[last edit: 4/26/2003 10:26:53 AM PST]

[Photos:]
photoWM CASEY NE

Cool building just southwest of this benchmark. It might be worth a visit.

[Photos:]
photoRecovered

Odd how several have logged the Washington Memorial, but none of them logged these benchmarks right at the base. Guess I get to be the first.

Documented History (by the NGS)

Unknown by RBNF (MONUMENTED)
11/10/1999 by NGS (GOOD)
DESCRIBED BY NATIONAL GEODETIC SURVEY 1999 (RWA) IN WASHINGTON DC, AT THE WASHINGTON MONUMENT, AT THE NORTHEAST CORNER OF THE WASHINGTON MONUMENT, AN IRON BAR SET IN THE FOUNDATION OF THE MONUMENT WALL, 7 INCHES SOUTH OF NORTH SIDE ON EAST WALL AND 7 INCHES BELOW THE SURFACE.

Control Text

  • The horizontal coordinates were scaled from a topographic map and have an estimated accuracy of +/- 6 seconds.
  • The orthometric height was determined by differential leveling and adjusted by the National Geodetic Survey in April 2000.
  • The geoid height was determined by GEOID99.
  • The dynamic height is computed by dividing the NAVD 88 geopotential number by the normal gravity value computed on the Geodetic Reference System of 1980 (GRS 80) ellipsoid at 45 degrees latitude (g = 980.6199 gals.).
  • The modeled gravity was interpolated from observed gravity values.

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