Why Is Baldur’s Gate’s Road Network Non-existent?

Am I missing something or what?

Looking at the Sword Coast map on D&D Beyond, Baldur’s Gate seems to have very few roads in or out of the city. There is no direct road northeast to Boareskyr Bridge or the Trade Way for example.

For such a big city, that seems strange. Surely not every traveller or caravan would take a barge along the Chionthar to Scornubel?

https://www.dndbeyond.com/resources/1782-map-of-faerun