Often refers to historical highways from the Edo period, but also used for modern main roads. The Edo-period connotation is strong in historical contexts.
The Old Tōkaidō was a major highway in the Edo period.
If you go straight along this main road, you'll reach the station.
Metaphorical use for a route to success or a career path. Often appears in compounds like 出世街道 (path to success) or エリート街道 (elite path).
See also: 出世街道 (しゅっせかいどう)
He is speeding along the fast track to success.
He has walked the elite path since he was young.
subdistrict (China)
Administrative division in China, equivalent to a subdistrict. Rare in everyday Japanese; mainly encountered in geographical or political contexts.
In China's administrative divisions, a subdistrict is at the same level as a township or town.
I drove along the old Koshu Highway.
After graduating from university, he followed the elite career track.
Old inns line up along the highway.
街道 is pronounced identically to 海道 but means a land highway or main road, not a sea route.
highway to success; fast track to promotion