I hadn't seen a panda before I visited the (the) Ueno Zoo.

Dear native English speakers,
I have two questions.
Q1 Which would sound right? I think (a) would be all right. But how about (b)?
(a) I hadn't seen a panda until I visited the (the) Ueno Zoo.
(b) hadn't seen a panda before I visited the (the) Ueno Zoo.
In this case, is "the" before Ueno Zoo optional?

Q2 Is "that" optional in this case? Is there a difference in nuance between the two?
(a) I didn't know he had moved to Nagoya.
(b) I didn't know that he had moved to Nagoya.

Thanks in advance.
Hirashin

1 (a) and (b) sound right. In this case "the" is an optional word. 2(a) and (b) are right. "That" is optional and there is no difference in nuance between the two. I'm pretty sure in the first sentence the word "that" is understood to be implied.