Seki or barriers were inspection stations originally erected to collect road-use taxes or to inhibit trade or free movement. In the Edo period, they were used primarily for security purposes. Travelers were channeled through the barrier and under the scrutiny of officials whose duty was, in general, to keep a watch on travelers and in particular to prevent weapons from moving toward Edo and samurai women from leaving Edo without permission. The weapons might be used against the government while the departure of women from Edo might encourage a daimyo to attempt rebellion against the government. Barriers in the Kiso Valley were also charged with watching for smugglers who dealt in the valuable lumber of the valley.
