The empire conducted trade with the Chechens through controlled channels. The number of state barter yards (points of exchange of goods under the supervision of officials) in the second half of the 1840s "was increased to 11"[1]. In 1850 the empire expanded trade - under the same control: historian N. I. Pokrovsky writes - "In 1850 the commander-in-chief, wishing to bring the unsubdued highlanders closer to the Russians, permitted the opening of a fair near the Groznaya fortress... After an exchange of amanats on 15 May an armistice of three days was concluded... On our side the sale of weapons and iron was not permitted" (an amanat is a hostage whom the empire took from a community as a guarantee of its submission)[2]; historians Ya. Z. Akhmadov and E. Kh. Khasmagomadov write of "the first Grozny trade fair," to which the highlanders brought "various goods on 500 arbas" (an arba is a two-wheeled cart)[1]. The fair opened with an exchange of hostages; the sale of weapons and iron the empire did not permit.