Walk in the Park DLC, Far Harbor Quest

This quest will be triggered or can be aquired when you complete Far From Home quest.

Stages of "Walk in the Park" quest

I've arrived in Far Harbor. The locals may know more about Kasumi and the synth refuge she mentioned.

Captain Avery, the leader of Far Harbor, has agreed to give me information if I help defend the town.

Creatures from the Fog are attacking Far Harbor. They need to be dealt with.

Kill the incoming monsters.

With the town secure, I can get more answers from Captain Avery about Kasumi and the synth refuge.

She will tell you that you should ask Old Longfellow for help. She will also give you new side quest Living on the Edge.

There's a hunter named Old Longfellow that can guide me to Acadia, where Kasumi was headed.

He is inside The Last Plank tavern.

There is an issue of Islander's Almanac on the table next to Old Longfellow. Grab it! It will add a few markers to your map.

Old Longfellow won't act as my guide unless I bribe him with whiskey. The bartender, Mitch, sells some.

If you didn't convince Old Longfellow to be your guide (charisma checks), then you will have to buy him a bottle of whiskey from bartender Mitch.

Old Longfellow will guide me through the dangers of the island to Acadia and hopefully Kasumi.

On the way to Acadia you will have to kill many enemies such as: trappers, ghouls, wolves, gulpers or mirelurks.

You will also meet a member of Child of Atom.

My guide, Old Longfellow, wants to have one last word with me before I enter Acadia.

From now, Old Longfellow can be your companion and you can use the workshop at Longfellow's Cabin.

I made it to Acadia. Hopefully Kasumi Nakano is still here.