As of 2006, the total number of Old Believers is estimated from 500,000 to 1 million, some living in isolated communities to which they fled centuries ago to avoid persecution. An Old Believer parish in the United States has entered into communion with the Russian Orthodox Church Outside Russia. Old-Believer churches in Russia have begun the restoration of their property, although Old Believers face many difficulties in claiming restitution rights for their churches. Moscow has churches for the most important Old Believer branches: Rogozhskaya Zastava (Popovtsy of the Belokrinitskaya hierarchy official center), a cathedral for the Novozybkovskaya hierarchy in Zamoskvorech'ye and Preobrazhenskaya Zastava where Pomortsy and Fedoseevtsy coexist.