The route of the King William Canal consisted of: the 700-meter Takgrabe Canal, the 20-kilometer Minija River, which was 26–40 meters wide and 1.6–3.0 meters deep; followed by an 8.2-km-long excavated canal to the Dreverna River; a 500-meter section of the latter was channelized, and a 15-km-long, 19-meter-wide, 1.6-meter-deep canal was excavated to Smeltė Bay. A towpath ran along the entire western edge of the canal.
Ten wooden bridges were built across the canal (the wooden bridges were replaced with metal ones in 1902–1904). Some of the bridges in the southern part of the canal were blown up during World War II. Currently, two bridges with metal structures and the remains of seven bridge piers have survived; these piers stood 5.15–5.65 m above the water. In the middle of the bridges were 1.25-meter-wide lift sections to allow room for the masts of passing ships and the funnels of steamboats.