Don't want sub-menu to appear

I've created a new Menu item (as I want a page for this item), but I don't want it to appear in my Menu list.
See attached image.
I want the menu item for 'Art Collector's Residence' (as I will hyperlink to the page from a photo on the Completed Projects page) but I don't want it to appear on my menu at the top.
Can I suppress it from the menu?
Thanks
Rich

Please look at template settings in 'Menu Settings' tab, you can specify 'End-level' for menu and cut the menu tree to some level.

Change from -1 (infinite) to 1 and it worked perfectly.
Thanks
Rich