To say I love castles would be to considerably understate the case.  But how to find a castle without a map?  Here are several great resources . . .

A map of castles in SW Wales:

This castle shows both the native castles and the Welsh ones.  Some of them are obviously close together, and this indicates a vassal/lord relationship among the barons, or just the passage of time, when a castle was destroyed, a new one was often built close by (if it wasn’t built right on top).

Native Welsh castles from the Castles Wales site (http://www.castlewales.com/native.html):

From the Welsh government site (cadw.wales.gov.uk):

Neither of these maps show the Edwardian castles that were either built right next to a destroyed Welsh castle or on top of one.  Neither shows Aber Garth Celyn either, which was Llywelyn ap Gruffydd’s seat, but wasn’t rediscovered until very recently.  For more about that, see:  https://www.sarahwoodbury.com/aber-castle-gareth-celyn/