Mapkit showing annotation region - iphone

I have a MKMapView with several annotations. These annotations differ from varios location all over Sweden. What I want to do is to zoom the map so all annotations show.
I do not want to position the map to my position (although I do want to show it), but want all annotations to show and center the map according those locations.
I.e. if one annotation would be "kiruna" (upper left sweden) and the otherone would be "stockholm" (middle right sweden), I want the map to show both. If the map would only show "uppsala" (above stockholm) and "stockholm", I want the map zo zoom that "uppsala" is in the top left and "stockholm" bottom middle/right.
How can I do this? I have the lat/lon positions ofcouce for every location.
Regards,
Paul Peelen

Dupe with plenty of material to solve your problem: Positioning MKMapView to show multiple annotations at once

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The key here is to leverage the latLngToContainerPoint() method of L.Map - it will give you the pixel coordinates relative to the map container of the L.LatLng passed.
So create a container for a tick...
<div id="topbar"><span id="toptick">↓</span></div>
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EDIT:
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Original answer:
The stack order of vectors (like your polygons) and Markers is fixed in Leaflet 0.x. They are inserted into "panes" which order is (from top-most to bottom-most):
popupPane
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