• Views from Penobscot Mountain summit.


    National Park Maine

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  • 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.

  • Bubble Pond Carriage Road closure

    Bubble Pond Carriage Road will be closed to all traffic Monday 9/15- Wednesday 9/17 from the parking lot to Triad-Day Mountain Bridge. More »

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?

Bronze statue of a Passamaquoddy man

Saint Croix Island International Historic Site is a National Park Service site located within three hours of Acadia. Saint Croix commemorates the first French attempt at a permanent settlement in N. America. Explore the mainland site with an interpretive trail featuring bronze statues and waysides. More...