All routes will take the riders through the stunning Pembrokeshire countryside at a time when the trees and banks are in full bloom.
Cyclists of all ages and ability are invited to participate; a seven-year-old boy is the youngest entrant so far, while very serious cyclists will undertake the 100K course. All money raised will go to Macmillan Cancer Support's South West Wales Appeal which will help to strengthen cancer care in this area.
The event is the brainchild of Lion Andrew Milward, who cycled for Wales in the 1970s. Andrew and his fellow Lions hope that this Cycle-Sportif will grow into a successful annual fixture like the sponsored horse rides at Lydstep and the Giant Paella event on the Harbour.
Lion Nick Stapleton recalls that their first horse-ride was not well supported, but, thanks to the Lions' hard work and word spreading, it is now a popular, fully subscribed event, which takes place twice a year.
Those who have not yet registered either on the website or at cycle shops throughout the county for Sunday's ride are still invited to join in.
Riders are asked to arrive early to register at Tenby Leisure Centre before 9 am. Riders must observe all traffic regulations and the Highway Code and are reminded that this is not a race.
Riders participate at their own risk. There is no liability whatsoever on the part of the organisers. Prizes will be awarded for the highest sponsorship, adult and junior, veteran and team, while there will be other spot prizes on the day.
Prize-winners will be notified individually.
Sponsorship monies will be presented to Macmillan Cancer Support and prizes presented to the riders on a date to be announced in the press.
For inquiries, telephone 07977 056352, while for details of routes and the opportunity to enter on- line visit http://www.pembrokeshirecyclechallenge.co.uk">www.pembrokeshirecyclechallenge.co.uk