To pick up your physical Japan Rail (JR) Pass after arriving in Japan, you must visit a designated JR Exchange Office (found at major airports like Narita, Haneda, and Kansai, as well as major train stations like Tokyo or Kyoto). You will need three specific things: 1) Your original Passport containing the physical "Temporary Visitor" entry stamp/sticker received at immigration (electronic copies or other visa types like "Student" are not accepted). 2) Your Exchange Order (voucher) that was mailed to you or purchased online prior to your arrival. 3) A completed JR Pass Application Form, which is usually available at the counter. If you purchased your pass directly from the official "JAPAN RAIL PASS Reservation" website, you will also need the Reservation Number issued at the time of purchase to verify your identity.