The Paschal cycle in the Eastern and Oriental Orthodox Churches, is the cycle of the moveable feasts built around Pascha (Easter). The cycle consists of approximately ten weeks before and seven weeks after Pascha. The ten weeks before Pascha are known as the period of the Triodion (referring to the liturgical book that contains the services for this liturgical season). This period includes the three weeks preceding Great Lent (the "pre-Lenten period"), the forty days of Lent, and Holy Week. The 50 days following Pascha are called the Pentecostarion (again, named after the liturgical book).