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2 Just corrected some grammar and a typo
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I would suggest allowing users a way to filter down their search based on what they are looking for; as this can help remove some of your markermarkers. 

When that is not enough how about combining symbols into onone marker, when the attraction/facility in a central location are too close to show a individual markers. Then as users zoom in the markers could be split up to better reflect location (when possible).

mockup

download bmml source – Wireframes created with Balsamiq Mockups

I would suggest allowing users a way to filter down their search based on what they are looking for; as this can help remove some of your marker. When that is not enough how about combining symbols into on marker when attraction/facility in a central location are too close to show a individual markers. Then as users zoom in the markers could be split up to better reflect location (when possible).

mockup

download bmml source – Wireframes created with Balsamiq Mockups

I would suggest allowing users a way to filter down their search based on what they are looking for; as this can help remove some of your markers. 

When that is not enough how about combining symbols into one marker, when the attraction/facility in a central location are too close to show a individual markers. Then as users zoom in the markers could be split up to better reflect location (when possible).

mockup

download bmml source – Wireframes created with Balsamiq Mockups

1
source | link

I would suggest allowing users a way to filter down their search based on what they are looking for; as this can help remove some of your marker. When that is not enough how about combining symbols into on marker when attraction/facility in a central location are too close to show a individual markers. Then as users zoom in the markers could be split up to better reflect location (when possible).

mockup

download bmml source – Wireframes created with Balsamiq Mockups