You will want a car to explore Olympic National Park. Unlike many national parks, there are no roads through the park. In fact, the central part of the park is one of the last great roadless patches in the lower 48 states. There are a number of roads running from US 101 into the park: Hurricane Ridge, Elwha, Sol Doc, Hoh, and Quinault. The park also includes much of the Pacific coast along the peninsula which is accessible from US 101 at Klalaloch, La Push, Cape Alava and Neah Bay. The park is a big park, so think about your trip, and take driving times into account. You don't want to spend all your time on the road.
There are a number of ways of getting to Olympic National Park by car:
From Seattle or Seatac - head south to Tacoma and cross the Tacoma Narrows to the peninsula
From Seattle - take the Bainbridge Island or Bremerton ferry
From north of Seattle - take the Edmonds ferry to Kingston and continue west
From Anacortes or Whidbey Island - take the Keystone ferry from Whidbey Island to Port Townsend and continue west
From Olympia or points south along the I-5 corridor including Portland - take US 101 north along the Hood Canal
from points south on the coast, following the coast - take US 101 north through Aberdeen and near Ocean Shores
from Vancouver or Victoria, BC - take the Coho ferry from Victoria
Most of the ferries are run by the Washington State Department of Transportation (http://www.wsdot.wa.gov/f...), but the Coho ferry (http://www.wsdot.wa.gov/f...) and the Victoria Express (http://www.victoriaexpres...) are run privately.
Be warned that the ferries can be backed up for two or three hours, particularly in the summer when people are heading off or returning from their vacations on the Olympic Peninsula. If you can, avoid heading west on Friday afternoons and east on Sunday evenings. The ferries usually run roughly every 50 minutes and can offer a relaxing way to cross Puget Sound.
I-5, the main road from Seattle to Tacoma can be crowded during rush hour 6-9 AM and 4-7 PM. You can check traffic conditions, and for other travel problems, at the state DOT web site (http://www.wsdot.wa.gov/t...).
There are scheduled flights to Port Angeles, so you can approach by air. The views of the Olympics are often fantastic, and you can arrange to rent a car at the airport.
- from Boeing Field BFI near Seattle - take a scheduled Kenmore Air (http://www.kenmoreair.com/) flight to Fairchild Airport CLM
Another approach is to fly to Victoria, BC YYJ, then take the Coho ferry or the Victoria Express to Port Angeles and rent a car there.
- from Victoria, BC - fly to Victoria, rent a car there, or take the ferry across the Strait of San Juan de Fuca and rent a car in the U.S.