Because they all probably used MIAMI alone as their location, its likely the pins are all at the geographic center of Miami.
Using a city & zipcode [esp w the added 4 digit locator after the zip) would be better and show pins more separated, even when in the same zip code. By adding the 4digit locator # after you zip should even separate pins in the same zipcode.
I often redact multiple pins people dont even know they posted, because for them the pins are stacked and they can only see the top most pin
This topic got moved to a boat topics forum sticky the other day & now its back as a resto forum sticky... odd... oh well the more exposure the better i figure
Have a great week all!
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