I've been in the following (roughly in order of visiting!):
HMS Alliance (Portsmouth, UK)
USS Pampanito (San Francisco, CA)
USS Nautilus (Groton, CT)
HMAS Onslow (Sydney, Australia)
HMAS Ovens (Perth, Australia)
Holland 1 (Portsmouth, UK).
I'm planning to go to Laboe and Hamburg next year to visit U-995 and U-434 (Tango class). I'm also thinking of planning a return to the US east coast to tick off a few more subs from my list
