@oristarA,
The proper word choice (or spelling of it) is '
through'.
Another correction for fixing would be in keeping with parallel voice and tense of the rest of the paragraph. The phrase should read "As I opened the door and passed through the doorway
, ... {
Edit: insert comma}". It should not read, "As I open ... "
FYI, the word 'threw' (past tense) means to toss or physically move something...for example, using your arm or arms.
You're correct. That was a typo and could be corrected to read as 'must-see' or 'must-visit'.