The Oyama Kaido runs southwest from Edo, roughly paralleling the Tokaido as it passes through the many farming villages that dot the lower reaches of the Tama river basin. The Oyama Kaido links up with the Tokaido at Odawara
Before Tokugawa Ieyasu moved to Edo, the Tokaido only went as far as Kamakura -- about 35 kilometers south of Edo. Back then, Edo was still a small town and the Oyama Kaido was the main road to get there. Nowadays, the Tokaido has become the main highway, but the Oyama Kaido is still often used by people going from the northern suburbs of Edo to Kyoto or western Japan.