Chiyoda Line Series (千代田線シリーズ)
Tokyo is a city blessed with what is often dubbed as the best public transportation system in the world. Tokyo's train and subway network is unrivalled - spotless, quiet and almost always on time.
The caches in this series are named after the stations along the Chiyoda Subway Line. For half a year, I lived outside a station on the Chiyoda Line. The trains on this line took me to football training, to go out, have dinner, explore and catch up with friends.
The caches in this series are camo painted centrifuge tubes. You are not required to venture far from the track for most caches. A number of caches have a letter 'code' used to calculate the coordinates to a final mystery cache. Collect these codes, rearrange and piece them together to make the name of the station on the line that I lived next to. This will be the keyword you can use to obtain the final.
About the Chiyoda Line (千代田線について)
The Chiyoda Line is the second busiest line in the Tokyo Metro network, on average carrying 1,447,730 passengers daily (2017). In 2015, the segment between Machiya and Nishi Nippori was the 9th busiest of any train line in Tokyo, with a crowdedness rating of 178%.
The Line is 24km long, with 20 stations serving through 6 wards (and is named after the Chiyoda Ward). The line, like many in Japan, features through services. From Ayase, some services run through onto the JR Joban Line Local Service to Toride, and from Yoyogi-Uehara onto the Odakyu Odawara Line to Hon-Atsugi and to Karakida on the Odakyu Tama Line.
WARNING: Snakes are prevalent in this area and there is a minor risk of unexploded ordinance within the Regional Park.

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