The Trinity Lavra of St. Sergius (Russian: Тро́ице-Се́ргиева Ла́вра) is the most important Russian monastery and the spiritual centre of the Russian Orthodox Church. The monastery is situated in the town of Sergiyev Posad, about 70 km to the north-east from Moscow by the road leading to Yaroslavl, and currently is home to over 300 monks. The unique architectural ensemble, which took more than a century to create, was listed by UNESCO in 1993 as a World Heritage Site. Bell Tower, commissioned by Empress Elizabeth,, at 88 meters, was one of the tallest structures built in Russia up to that date.