Who hits the most number of sixes in a single innings in test cricket?

A lower-order batsman and Swing Bowler Wasim Akram from Pakistan holds the record of most number of sixes in a Test innings.  He hit 12 sixes against Zimbabwe in one innings. At the end of innings he scored a total of 257 runs with 22 fours and 12 sixes. Nathan Astle of Newzland stands in second place with 11 sixes in a single innings of test match.