How is ammonia manufactured industrially?

(N/A) Ammonia is manufactured on a large scale by the Haber's process.
$N_{2(g)} + 3H_{2(g)} \rightleftharpoons 2NH_{3(g)} \quad \Delta_{f} H^{\circ} = -46.1 \, kJ/mol$
The optimum conditions for the production of ammonia are:
$(i)$ Pressure: $A$ high pressure of about $200 \times 10^{5} \, Pa$ $(200 \, atm)$ is maintained to shift the equilibrium in the forward direction.
$(ii)$ Temperature: An optimum temperature of about $700 \, K$ is used.
$(iii)$ Catalyst: Iron oxide with small amounts of $K_{2}O$ and $Al_{2}O_{3}$ is used to increase the rate of attainment of equilibrium.