You can choose whether or not to show a site marker on the map or aerial photograph to help you find the location of your site. See To select a map layer and marker style
You can subsequently delete it from the map.
•To remove the site marker just from the map or aerial photograph you are currently viewing, click it once and press Delete on your keyboard.
It will still appear on other map layers unless you deselect the site marker option on User Settings dialog box. See To change General Settings