I'm planning a trip to Iceland which involves a lot of research to gather information from different sources (mainly blogs, but also travel guides and other).
The problem with Iceland is that almost all tourist attractions are natural and not all are indicated properly. For instance, if I want to go to "Hellulaug" (because I've seen some interesting pictures), I have some work to find where exactly it is located (there are no maps that mark it with precision and I don't have enought time during the trip to find it).
Given this, at the beginning I have started to put POIs (Points of Interest) in a Google Maps Engine but soon I've reached its limits: only 3 layers and only 20 personalized points per layer. So, I'm wondering if there is a planning tool or online map that allows to add POIs into a map (existent or new ones) without limit and free.