Turnagain Arm · Head of the arm
Portage Valley & Whittier
Glaciers at the head of the arm, the one-lane tunnel, and Prince William Sound
Location
Head of the arm · MP 79 turnoff
From Anchorage
~50 mi / 1 hr
Highlights
Portage & Byron glaciers
Beyond
Whittier & Prince William Sound
At the eastern head of Turnagain Arm, Portage Valley opens into a glacier-carved basin of lakes, ice, and rainforest. It's home to Portage Glacier, the Begich-Boggs Visitor Center, and short trails to hanging ice — and the gateway, through a remarkable shared road-and-rail tunnel, to the port town of Whittier and the glaciers of Prince William Sound.
Live tide timing
Next good bores
Tomorrow
Mon, Jun 29
Tuesday
Tue, Jun 30
Wednesday
Wed, Jul 1
Thursday
Thu, Jul 2
Times for Hope / Mile 13 · arrive ~20–30 min early. The mudflats are deadly — stay on the gravel above the waterline.
Featured partner
Advertise to bore tide visitors
This spot reaches people actively planning a bore tide trip to Turnagain Arm. Perfect for surf schools, wetsuit rental, Girdwood lodging, guided tours, or gear shops.
Inquire → [email protected]Portage Glacier & the visitor center
The Begich-Boggs Visitor Center sits on Portage Lake with exhibits on glaciers and the valley's ecology. Portage Glacier has retreated out of direct view from the center, but boat tours on the lake bring you to its face among the icebergs, and the short, easy Byron Glacier trail leads toward another ice field.
The Anton Anderson tunnel
Whittier is reached through the Anton Anderson Memorial Tunnel — a one-lane, roughly 2.5-mile passage shared by cars and the Alaska Railroad, among the longest highway tunnels in North America. Traffic alternates direction on a schedule and pauses for trains, so check the tunnel times before you go.
Whittier & Prince William Sound
On the far side, the small port of Whittier is the launch point for day cruises into Prince William Sound — calving tidewater glaciers, sea otters, seals, and seabirds. It's also a stop on the Alaska Railroad's Glacier Discovery train if you'd rather not drive the tunnel.
Pro tip
Check the Anton Anderson Tunnel schedule before driving to Whittier — it's one lane, alternates direction, and closes for trains. Pair Portage with the Wildlife Conservation Center at MP 79; they're minutes apart.
For business owners
Put your Portage tour on the map
Whittier glacier-cruise captains and Portage-area tourism businesses can reach visitors planning their Prince William Sound trip with an official Last Frontier Events listing.
More things to do nearby
Alyeska Resort
Alaska's premier mountain resort — 15 minutes up the arm from the bore
Ride the Alaska Railroad
The Glacier Discovery train along the arm — and the only way in to Spencer Glacier
Whitewater Rafting on Sixmile Creek
Class IV–V glacier canyons by Hope — and gentler floats nearby
Alaska Wildlife Conservation Center
A nonprofit refuge at the head of the arm — and the herd that brought wood bison back to Alaska
Bird-to-Gird Bike Path
13 paved, traffic-free miles along Turnagain Arm between Indian and Girdwood
Hiking Out of Girdwood
From the historic Crow Pass to easy rainforest waterfalls