Really you need a couple of visits at least to take it all in , but if you only have a day and you want to see the very top highlights , the first thing to do when you enter the museum is to go straight ahead , right through the atrium , until you get to the other end , where the Amarna gallery ( room # 3 ) is dedicated to the reign of one very special pharaoh , Tutankamun 's father , the heretic king Akhenaten .