• Views from Penobscot Mountain summit.


    National Park Maine

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  • Temporary Road Closure

    A section of the Western Mtn Road in Southwest Harbor will be closed until 8/18 while park crews replace a culvert with a new fish-friendly open bottom culvert. For more information and a map visit our Getting Around Page. More »

  • Trail Closure: Gorge Path weekdays, 7 am - 4 pm

    The section of the Gorge Path between the Hemlock Path intersection and the A. Murray Young Trail intersection is closed until rehabilitation work is completed. The closure will be in effect Mondays through Fridays only, from 7 am to 4 pm.

Field Guide to Algae - Benthic Diatom

Navicula growing on rock

Navicula sp.
Navicula sp. is a tube-dwelling diatom that is particularly abundant in spring from the high to the lower intertidal zone. The outer covering of each diatom, which is a single cell, is made of two silica valves (“shells”); diatoms live in “glass houses.” This diatom often fools experts, because it can look like a filamentous brown alga.

Photos by Sarah Hall.

Did You Know?

Image of the Guide's Guide cover

The Guide's Guide to Acadia National Park, originally created to share important information about the park's facilities and natural and cultural resources with commercial guides, is available to the public on this website. The guide contains everything you would want to know about the park. More...