2010-10-25 39 116

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Mon 25 Oct 2010 in 39,116:
39.9375992, 116.1934044

peeron geohashing.info google osm bing/os kml crox


北京市石景山区八大处路45号 (45, Badachu Road, Shijingshan District, Beijing, China)




I had planned to visit the ancient observatory but it closed early that day so that plan had to be cancelled. (40 minutes would have made the visit too short anyway, as I found out the next day when I returned there...)

Having now some spare time I decided to have a closer look at the coordinates, which I remembered as being in some western suburb. When I noticed that the hashpoint was "probably reachable" (see Google maps issue below) and within walking distance of Pingguoyuan ("apple garden"), which is the western terminal of subway line 1, I quickly printed out a map of the area between the station and the hash, grabbed the day's geohashing gear (GPS, camera and public transit card) and set off.

While on the subway I had plenty of time to enter the coordinates on the GPS. Since I was leaving the city center, there were fewer people after each station and I was eventually even able to find a seat.

After an uneventful ride I reached the terminus and went back up in the open air. I started walking northeast between residential buildings until I reached Pingguoyuan Street. I still had about 2 km to walk, it was already getting dark, and I was not sure yet whether this would have to be another Ambassador Geohash, so I jumped into a taxi that just stopped in front of me to drop someone and showed the driver where I wanted to go. The hashpoint being conveniently located along a N-S oriented street allowed me to tell the driver exactly where to turn left despite the lack of street-level China maps on my GPS (the map printout did not help, see below).

I then proceeded to cross the street (this is not recommended if you are over-sensitive to adrenaline), and enjoyed the hash getting closer and closer on my display... If you look at the aerial view, you will notice that the hash is on a thin white stripe, separated from the street by a wide green stripe. The large building which is visible is the Shougang NEC Electronics (首钢日电电子, SGNEC) manufacture, you can see it on their website. Well, and the white strip is a fence. With security cameras, and guards.

At that point, I was more or less facing the hash from the street, and the GPS indicated about 9 m left. I wasn't sure which side of the fence that would mean, so I thought I'd start with asking for permission to enter. It wasn't very easy to be understood with my very limited Chinese, but I managed to explain that I wanted to get inside to take pictures of the trees along the gate (which was factually true). That wasn't met with much enthusiasm. I proposed then that the guard or one of his colleagues could come with me, but unfortunately he told me that it was not possible for them to let a foreigner (in the sense of someone from a foreign country) in... I thanked him anyway and quickly retreated. No Ambassador achievement today...

I then went back to check whether the hash could still be claimed as successful. When I was about 1 m away from the fence, the GPS showed 3.5 m left to the hash, with an accuracy of 5 m. Combined with the fact that Google shows the location as being on the fence, I consider the coordinates as having been reached. I could have tried to get better numbers, but I really didn't want to stay there longer, despite the guards now knowing that I wanted to take pictures of their trees (or maybe _because_ of that).

I then walked back to the station, which was easily found by walking in the opposite direction to everyone else...

Google maps problem[edit]

There is a discrepancy between the satellite view [1] and the map view [2]: the same coordinates will not show at the same place. This is a known issue, see for instance this discussion on the Google maps website.

If you use the Chinese version of Google Maps, the location on both views ([3] and [4]) match, and corresponds to the location on [5]. But for having been on site with a GPS receiver, I can confirm that the only correct location is the one displayed by the satellite view on maps.google.com. The taxi driver was actually surprised when I told him not to turn left yet: he was following the directions on the google maps printout, while I was looking at the GPS receiver...

It is worth noting that OpenStreetMap shows the hashpoint where it really lies.


3.52 m left (you can see the "planning page" in the background) 
5 m accuracy 
The hash is there! The flash accidentally fired, so much for being discreet... 
The main entrance, with the security staff.