Enjoy a St Trinians-themed family treasure hunt as part of the Chiltern Heritage Festival. It’s 1966 and a criminal mastermind has stashed stolen money in a secret hideaway. Can Chinnor’s young detectives solve the case and discover where the cash is hidden? But look out, those pesky St Trinians Girls are on the case and may try to mislead you. Book an all-day travel ticket and you can take several train trips during the day, both by steam and vintage diesel.