Originally Posted by
Wally Bird
They go through US waters.
The 49th parallel is only the border until slightly west of the peninsula where Tsawassen is located. Point Roberts WA is a US community at the southern end of the Peninsula, accessible to mainland Washington state only via Canada if going by land.
The border zigs and zags a bit to split the Southern Gulf islands (Canada) from the San Juan Islands (US).
The Tsawassen (Vancouver) - Swartz Bay (Victoria) ferry does travel through US waters for only a short time, either just after leaving Tsawassen, or just before arriving, depending on trip direction. Of the 1 hour 35 minutes sailing, only about 10 minutes is in US waters.