Metropolis is the 1926 film by Fritz Lang and contains some of the most forward-reaching and futuristic visions of city life of its time. This imposing film has some of the most impressive scenery and visuals of any production of its time.
For me it seems to have a very strange sorts of surreal, almost Steampunk vibe about it. Albiet one closer to the high-rise horror of modern Asian cities then the Victorian romanticism we're used to.
Its inspiration seems to come mainly from the New York and Chicago skylines of its era taken to a whole other level, adding huge sun-obscuring gaints with great churning machines in its underbelly.
For those who haven't seen it yet I would thoroughly recommend it for its subversive take on the optimistic views of the future during that decade.