Sharkfin Tower is located along the ridge of peaks extending from Forbidden Peak to Boston Peak to Sahale Peak. It boasts good rock with excellent exposure with an alpine setting that makes Boston Basin one of the most beautiful places in the world to climb. The two popular routes include the moderate Southeast Ridge, rated at 5.0, and the Southeast Face at 5.10. A 30 degree snow slope in the approach gully adds to the alpine feel of the climb. The summit affords excellent views of Eldorado Peak, Forbidden Peak, the north face of Mount Buckner, Boston Peak, Johannesburg Mountain and Sahale Peak.
In July of 2005 three climbers were killed on their descent from Sharkfin Tower. One of the group leaders had been injured by rockfall and while other members of the party were tending to her wounds a second rockfall occurred leading to a combined total of three deaths. The group outing was an instructional climb put on by "The Mountaineers" out of Seattle.
From Interstate 5 in Burlington take WA 20 (North Cascades Highway) towards Sedro Woolley. Drive 47 miles to Marblemount and then get off on the Cascade River Road. Take this for 22 miles to a turnout (elevation 3,200 feet) beneath the impressive Northeast Face of Johannesburg Mountain.
Follow the climbers trail (originally a road to the Diamond Mine .75 miles above) to the vicinity of the mine site and then traverse open slopes. The climber’s trail is wiped out due to a large avalanche slide from Spring 2002. A level traverse across the debris will allow one to regain the climber's trail. The area as of mid - July had cairns marking the route and several branches and loose trees had been cleared to define a path across the second slide area encountered on the approach. Continue North for approximately a half mile through this area and cross four streams. A switchback trail leads to a moraine at 5,300 feet where multiple campsites and a compost toilet are located. a second camping area is located at 6,400 feet but remains snow covered until later in season.
Permits are required for overnight trips in the North Cascades National Park. For information call the National Park Service Ranger Station for the North Cascades National Park in Marblemount (360)873-4500.
June-September. Access to the Cascade River Road begins in late spring.
There are two standard camping areas in the Boston Basin Area below Sharkfin Tower. One is located at a little over 5,000 feet and the other a little over 6,000 feet. Both have compost toilets.