And what about "...was rebuilt..." or "...was rebuild..."?

Having checked here: http://www.thefreedictionary.com/build I'm lead to believe that "... was built" is the correct form, but if you do an internet search on "was build" you'll see that people use that form as well.

I believe it is "was built". I did a search using google, and most of the places I saw "was build" being used were ones discussing "builds" of various programs. I even found a site where someone corrected someone's use of "was build," lol.

"Built" is the past tense of "build." The word "was" indicates something that has already occurred, hence, in the past. The correct usage is "was built."

Was built. ;)