i have a question about page flicker effect on this website
http://www.adventurequeenstownnz.com/

when a link is clicked to open another page before the entire content appears the content moves to the right and then appears normally

any reason why this page flickering happens and how to avoid it

It would appear that it is simply changing pages causing the flicker. The content moving can be caused by the css loading. If you look at my page, when you first load it, the font in the main menu flickers and changes while the page is loading the font.

A way to get rid of the flickering would be to use AJAX to fill the content of the page. By doing this, you would no longer be loading a new page, just loading new content into the content container within the page. However, I'm not sure if it is a very search engine friendly way of achieving your goal.

2 things I see - 1, you're using nasty tables for layout, 2, you're using includes which must load. First thing I would recommend is to get rid of the tables for layout, that will go a long way in cleaning things up and minimizing that load flicker.