<prompt> Translate the following text to EnglishMwaka 1940 vijana wanne walipokuwa wakimfukuza mbwa walivumbua michoro hiyo yenye kuvutia ya ngombe, farasi, mbuzi, nyati, na nyati, ambayo ilikuwa imefichwa na kuhifadhiwa kwa miaka 17,000.  <response>: Concealed and protected against atmospheric changes for 17,000 years, these awe-inspiring frescoes and engravings of bulls, horses, ibex, bison, and deer were discovered by four teenagers chasing a dog in 1940. 