Chance to visit an ancient spring.
Taffs Well, a 12ft deep, warm water well which gave the village its name, had been left in a state of disrepair since the 1800s.
It is thought to have been used as a spa bath by the Romans because of its healing capabilities, curing ailments such as arthritis. But over many centuries it fell into ruin and, despite a number of attempts to renovate it over the years, it has remained concealed.
Residents even organised a petition in a bid to revive the well and increase tourism in the village.
And now, as part of Rhondda Cynon Taf Council's Open Doors heritage month, the mystery surrounding the well's mystical past can be revealed thanks to an open day on Saturday.
At 11am, local expert Gareth Farr will give an illustrated talk on the thermal spring at Taffs Well Bowls Pavilion, discussing its origins, geology and past. It will be followed by a visit to the spring.
Rhondda councillor Robert Bevan said: "The opportunity to visit the historic thermal spring that gave the village of Taffs Well its name is one not to be missed."
Call 01443 744044 or visit heritagetrailsrct.co.uk
* A special open day on Saturday will reveal the secrets of the Taffs Well spa