"Long Distance" proximity alerts?

Setting any Proximity Alert can be done by loading the POI in Manual Mode with POI Loader and setting whatever alert distance that you want. You set the prox alert for each POI individually, so you can have different distances for each.

I caution you to be careful about setting the prox alert to large. There could be several campgrounds, in close proximity and you are going to get multiple alerts that might end up driving you crazy. There are often rest areas within a couple miles of each other and even in my case when I set the alert at about 1 1/2 mile, I still get alerts for the rest areas on either side of the road.

If you're visiting a campground, why don't you just load the POI file without the alerts, then simply set the specific campground as a destination? The GPS will guide you there. If you then set the Rest Areas with 1 or 2 mile alert distance, you will be alerted as soon as you get close, to one.

See http://www.poi-factory.com/node/28650 for max setting.

I am going to make an assumption based on my own experience. Campgrounds are not going to be on the "road" you would be traveling through a particular state.

This is important because an "along the road" proximity alert requires that the location triggering the alert be within 30 meters of the road. On the other hand, a TourGuide alert will activate whenever you come with a circle with the location at its center.

see Comparing Alerts - Speed, Along The Road, And TourGuide
There are several FAQs on creating TourGuides.

Making CSV Files into TourGuides – And Their Many Different Uses

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