Translation of "I have been in london" in German

Since the beginning of 2012 I have been in London.
Seit Anfang 2012 bin ich in London.
ParaCrawl v7.1

I have been to London in between...
Inzwischen bin ich schon wieder in London...
ParaCrawl v7.1

I have been sightseeing in London several times, and visited places like the Tower of London, Madame Tussaud's, and Westminster Abbey.
Ich war schon mehrmals auf Sightseeing in London, und habe dabei schon einige "Klassiker" wie den Tower von London, Madame Tussaud's und Westminster Abbey erkundet.
ParaCrawl v7.1