Metropolitan Line: No service between Moor Park and Rickmansworth and SEVERE DELAYS between Rickmansworth and Chesham / Amersham due to a signal failure at Moor Park. Tickets are valid on Chiltern Railways. GOOD SERVICE on the rest of the line. If travelling from Amersham or Chesham towards Central London please take the first train and change at Croxley for onward services towards Central London.