The phrase "route along which" is grammatically correct and can be used in written English.
It is typically used to describe the specific path or direction someone or something follows. Example: The hikers took the winding route along which they passed through a dense forest and a steep mountain pass before reaching the summit.
Thousands of antigovernment protesters demanded Thursday that Pakistan shut the route along which supplies are ferried to American and NATO forces in Afghanistan.
Ms. Smith returned to Charter Oak Terrace while researching the book, walking the route along which the killer had dragged her friend.
The bomb exploded on a street connecting the mosque and the cemetery, a route along which Shiites from around the country carry relatives' bodies for burial.
A portion of El Camino del Diablo ("Devil's Highway"), the historic Spanish route along which hundreds of miners and pioneers lost their lives, crosses a corner of the monument and can still be traveled by four-wheel-drive vehicles.
They especially relished the walkway that runs along the island's western rim, a popular route along which strollers and bench sitters could admire the Manhattan skyline while perched beside the water.
Here the road roughly follows the route along which the Empress Dowager Cixi fled when allied Western armies invaded China in 1900 to relieve the siege of Beijing's embassies by xenophobic Boxer rebels.
For centuries we were connected only by long and dangerous caravan routes along which we traded spices, silk – and myths.
The three routes, which connect Far Rockaway to Long Island, are among 47 of 54 routes along which service might be reduced, according to Long Island Bus officials.
Faced with violence and the trampling of crops, the international NGO Practical Action came up with a sub-grassroots scheme to clarify the routes along which the cattle and camels are allowed to roam.
Being a practical man of the world, Watkins decided that these alignments represented ancient thoroughfares, routes along which goods such as salt, and craftsmen like flint knappers, traversed the countryside.
Not by chance is this a region crisscrossed by historic roads, whether they be the wide, grassy tratturi -- the hundreds of miles-long routes along which sheep made the seasonal journey from the mountain pastures of Abruzzo to the Apulian plain -- or the basalt-paved Via Appia, the consular road down to Brindisi, where the Romans launched their ships for the East.
