The Lost City of Gold
Allan Quartermain and the Lost City of Gold may be recognized as a 1987 movie starring Richard Chamberlain (of Doctor Kildare fame to those of us who can remember that far back!) and the delectable denizen of San Francisco - Sharon Stone. The title is in fact so popular it seems almost everybody uses it - two extreme examples being "The Lone Ranger and The Lost City of Gold" and "Lara Croft and The Lost City of Gold".
It is, of course, a sequel to 'King Solomon's Mines' and and was written by H. Ryder Haggard. Both are rattling good adventure stories set in the Africa that so intrigued the writers (and readers) of the times.