I have been playing a lot with various unicode characters recently. (For a result, see Ingy Ding MCD, a font with over 1400 characters.) Among the thousands of symbols with assigned unicode numbers are these three:
What are they?
Sometimes what you see depends a great deal on what you expect to see. What do you see in these symbols? Some people see gun sights or cross hairs. These happen to be unicode characters:
Circled plus ⊕ unicode 2295
Position Indicator ⌖ unicode 2316
N-ary circled plus operator ⨁ unicode 2A01
as they appear on my computer.
The position indicator is meant to show exact location. Given that there is a symbol meant to show exact location, one should not be too surprised to see it used on a map. But there are exceptions, and those exceptions may tell us more about what people expect to see than anything else.
(If you want eliminationist rhetoric on a map, a delete right or a delete left, the ERASE TO THE LEFT ⌫ unicode 232B or ERASE TO THE RIGHT ⌦ unicode 2326 seem more appropriate. As for a gunsight, I think a symbol that looks like a gun sight is unicode 2324 ⌤ The "UP ARROWHEAD BETWEEN TWO HORIZONTAL BARS" or enter key symbols fits.)
A great place to explore unicode other than unicode.org is www.fileformat.info