It did mention somewhere it was also valid in the Kamakura area to the Buddha. JR routes between Shinjuku and Kamakura: Suica.
Enoshima Electric Railway [Enoden] between Kamakura and Fujisawa: PASMO.
Suica and PASMO are compatible as to their e-money systems for fare payment and for shopping.
With a Suica card / a PASMO card, you can take a ride within Suica - PASMO network, changing railroad operators three times or less.
There is no discount to fares in principle, but if plural routes are presumable on your ride when you exit the network, a fare for the cheapest route among routes by least operators applies.
- PASMO Use Guide for travelers (PDF file):
http://www.pasmo.co.jp/en/pdf/pasmo_traveler_E.pdf(The network map in this guide doesn't show all the stations).
A Tokyo Metro pass covers sections on 9 Tokyo Metro lines, does not cover sections on 4 Toei Lines with line symbols A, I, S, E.
- Tokyo Subway Route Map (PDF file):
http://www.tokyometro.jp/global/en/service/pdf/routemap...From Shinjuku area to Asakusa Sta. of Tokyo Metro:
Fare: 230 yen per adult; Time: about 40 minutes.
Nishi-Shinjuku (M07) / Shinjuku (M08) / Shinjuku-sanchome (M09)
| Tokyo Metro Marunouchi Line
(M13)
Akasaka-mitsuke (G05): The same platform
| Tokyo Metro Ginza Line
(G19) Asakusa
I guess this route is the best as to transfer.
When you choose Ginza Sta., you have to go on a passageway above another Hibiya Line platform to make a transfer between the two lines.
From Shinjuku area to Akihabara Electric Town:
Maybe JR Yamanote Line's outer loop (via Ikebukuro) is better than JR Chuo & Sobu Lines. When you choose the latter, it may take a bit long to find Akihabara Electric Town Exit in Akihabara Sta.
Most shops selling electrical goods in Akihabara are on the west side of Yamanote Line. If you hope to see also shops on the east side, then your options include Metro route mentioned by AK. From Hibiya Line (H15) Akihabara Sta. platform, you can get out at Exit 3, taking elevators 2 times.
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