Altering a nav bar created in iWeb

I am helping a non-profit maintain this website: http://gopalmerpark.org/gopp/Welcome.html which was built in iWeb. I have made text changes in GoDaddy's html editor but need to remove one of the buttons from the top nav bar. I know there are a number of files working together there but am thinking there should be one where I can delete the now useless button, but I can't tell where that button lives. I've looked in the java files and in css files and everything I see related to nav bar. Any suggestions would be appreciated.

I am on a macbook pro retina, 2.3 Ghz intel core i7, running Yosemite 10.10.3 and have Dreamweaver.