Following a spike in demand from customers, Chiltern Railways has announced an increased timetable for the 121 Bubble Cars before they retire.

The TOC’s last two remaining Class 121 trains were first brought into service in 1960 and later bought by Chiltern in 2003, but – with maintenance costs increasing – the decision was made in March to put them into retirement.

The last day of service will be on May 19 from which point the Bubble Cars will be put up for sale.

Famed for being the last trains in service that use vacuum brakes, the single-carriage trains are recognisable for their small size and open environment which allow customers to see ahead through the train’s front windows.

Since 2003 the two trains have serviced the 18-minute journey from Princes Risborough to Monks Risborough, Little Kimble and Aylesbury, in Buckinghamshire.

Managing director of Chiltern Railways Dave Penney said: “Since we announced the retirement of the class 121 Bubble Cars in March, we’ve been inundated with requests from rail enthusiasts and members of the public wanting to take a last ride.

“As we near their final day, we anticipate even more interest so we have added additional services out of peak time to accommodate the extra passengers.”

On the final week of service from May 15 until May 19 there will be one additional service per day departing from Aylesbury at 16.39 and arriving at Princes Risborough at 16.53. This is in addition to regularly scheduled services during peak time.

On the final day of service on May 19 – which will be marked with a short ceremony at Princes Risborough station at 12.15pm – there will also be these additional services:

(Place of departure, departure time, arrival time)

Princes Risborough to Aylesbury 12.50, 13.04

Aylesbury to Princes Risborough 13.19, 13.33

Princes Risborough to Aylesbury 13.50, 14.04

Aylesbury to Princes Risborough 14.19, 14.33

Princes Risborough to Aylesbury 14.50, 15.04

Following their retirement the number of services running daily will remain unchanged.