The Conformist certainly has a brilliant cinematographer,Storaro-his work on The Sheltering Sky( an admittedly flawed film, but those nocturnal camel caravans and dunes!)and Apocalypse Now is also superb.
Other films which come to mind for their visuals;The Colour of Pomegranates(British spelling!)-"Cola" is right to praise it so highly. 2001:A Space Odyssey, Kwaidan (gorgeous colour and sets),Mirror(Tarkovsky),Sunrise.Several Mizoguchi films are absolutely beautiful;Sansho the Bailiff,Ugetsu Monogatari,The Life of Oharu,Tales of the Taira Clan(for its colour)... Some Visconti films are extremely sumptuous.I found Maborosi(Hirokazu Kore-eda)and Ozu's Tokyo Story also wonderful in a much subtler way.Claire's Knee is lovely,helped by the scenery.Of British films,Powell/Pressbuger's are probably the most impressive visually(The Red Shoes ballet the highlight).Vertigo,The Searchers,and some of the sequences in Singin in the Rain and The Band Wagon are memorable, as are some of Ophuls' masterpieces:Madame De, Letter from an Unknown Woman etc.Oh, and The Night of the Hunter (how did the A.F.I.100 leave it out?)   