Getting to Seattle by Road - 2 Interstate Highways
There is a very good network of interstate highways in the USA. These highways are generally designated by the letter 'I' and the suffix is the corresponding number of the highway. The even numbers are given to those Interstate Highways that generally go in the east-west direction and those highways that go in the north-south direction generally have odd numbers. The Interstate highways are generally bigger than the State highways and they are also identified by giving a number such as Highway 202.
Seattle is served by two major interstate highways. One of the highways is I-5. This highway goes in the south direction to Portland and in the north direction to San Francisco (California). Another highway is I-90. This highway connects Seattle with the eastern and the western parts of Washington. The highway also passes through Spokane while going towards Chicago and Boston (Massachusetts).
http://www.iexplore.com/cityguides/Washington/Seattle/Do's+and+Don'ts
Speed limits are 32kph (20mph) in school zones, 40kph (25mph) in urban streets, 80kph (50mph) on county roads and 97kph (60mph) on state highways. Higher maximum speeds are posted on some parts of the Interstate highways. On these highways, all the national licenses acceptable but most of the times an International Driving Permit is preferred. One can purchase US insurance from either the car hire company or the customs point and it is mandatory.
