1 Answer. That particular Point of Interest gave me some trouble as well. Luckily, one of my guild mates helped me out. There is a cave on the adjacent island that you must swim into to reach your point of interest. It should be in the general vicinity of the heart on that same island, as illustrated by this freehand circle.
You can get the vista without doing the event; but to get the skill point (and complete the map) you have to do the event. If you try and jump/sneak/fall/glitch in the game will simply port you out. This is new. Before you could just go down and get it. Also, worth noting that HoT has frequent "hero point trains" where people lead a group through the map kicking over all the hero points en masse. This can be good for you, as you can get an easy hero point boost while focusing on staying alive in the swarm of players and not having to really make sense of the madness that is Heart of Thorns.
These are called "Notarized Scroll of Maguuma/Desert Heroics" and will give you 10 hero points for the character you're playing on when you purchase it from the WvW vendor, so if you buy 5 of them, you'll get 50 hero points for that character. This just means that the challenges will be completed for you in the open world and you didn't need to

They're mostly in HoT maps. Base game map HPs are extremely easy and only give 1 point, so trains aren't worthwhile there. PoF HPs are also much easier than HoT ones, but rewarding enough that you'll occasionally see trains for them.

Interactive map (Upper level) The Pile of Guano is a large pile of bat guano found in the Canopy over Pact Encampment, west of Last Leap Point of Interest. It is the trigger for Defeat the vampire beasts hero challenge . After this challenge has been completed for hero points, it can then be activated and completed daily for map currency O33DaAC. 260 183 754 954 930 898 74 261

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