CREATE TABLE table_11805 ("Race" TEXT, "Circuit" TEXT, "Date" TEXT, "Pole position" TEXT, "Fastest lap" TEXT, "Winning driver" TEXT, "Constructor" TEXT, "Report" TEXT)

What circuit did Juan Manuel Fangio have the fastest lap at the german grand prix?
SELECT "Circuit" FROM table_11805 WHERE "Fastest lap" = 'juan manuel fangio' AND "Race" = 'german grand prix'
SELECT "Circuit" FROM "table_11805" WHERE "Fastest lap" = 'juan manuel fangio' AND "Race" = 'german grand prix'