Westminster Abbey is expected to open its new visitor centre, the King Charles III Sacristy, in early 2027.
The centre will house visitor welcome, security and ticketing facilities and will stand on the site of the medieval Great Sacristy, which was built in the 1250s during Henry III's reconstruction of St Edward the Confessor's Abbey.
The Great Sacristy was used by monks to store vestments, altar linens and other sacred items used in worship.
It was lost following Henry VIII's dissolution of the monasteries in the 16th century. The building was later converted into domestic accommodation but had fallen into disrepair by 1740 and was demolished. It is the only part of Henry III's church to have been lost.
The original structure and its foundations were rediscovered in the 1860s during excavations later featured on Channel 4's Time Team.
According to Westminster Abbey, worshippers and visitors using the new Sacristy will enter through the Great West Door, following the route traditionally used by royalty.
The Abbey said: “They will enjoy magnificent views the full length of the church and be inspired by the Abbey as it truly is: a House of God and a House of Kings.”
The new building has been designed by the Abbey's Surveyor of the Fabric, Ptolemy Dean. It will be constructed in a Gothic style using natural and durable materials, including locally quarried stone and sustainably sourced oak.
Queen Camilla laid the foundation stone for the King Charles III Sacristy in May 2025.
At the ceremony, she said: "God willing my husband and I will be back here again to open the King Charles III Sacristy.”