Birmingham's two Anglican bishops are setting off on a 280-mile walk around the West Midlands on Wednesday.
The walk marks the centenary of the Diocese of Birmingham
Rt Revs John Sentamu, Bishop for Birmingham and John Austin, Bishop of Aston, will visit hospitals, schools and churches during the Lent trek.
The two bishops will begin their journeys from Worcester and Lichfield respectively, but walk the rest of the route together from Thursday.
They aim to visit every church in the diocese by 20 March.
Bishop Sentamu is setting off from Worcester Cathedral at 0900 GMT, and will ride pillion on a motorbike until he reaches the boundary of his diocese, near the Lickey Hills.
From there, he will walk through Longbridge, Northfield, Bournville and Edgbaston to Birmingham Cathedral, where there will be an evening Ash Wednesday service.
Bishop Austin will leave Lichfield Cathedral and begin his walk at the diocesan boundary, near Sutton Park.
He will walk through Boldmere, visiting St Michael's church, Short Heath, Erdington, then underneath Spaghetti Junction and along the canal to the city centre.
He is due to arrive at the cathedral at lunchtime.
The choice of departure points recognises that the Diocese of Birmingham was made up of parts of the Diocese of Lichfield and the Diocese of Worcester, when it was formed on 2 March 1905.
A special cathedral service will mark the actual centenary of the founding of the diocese.
The bishops will be visiting schools, hospitals and universities as well as nearly 200 churches along the way.
They hope to raise money for the Bishops' Centenary Appeal Fund.