We will be in northern Spain in March 2023 and want to see some coastal areas near Santiago de Compostela. Both A Coruna and Pontevedra look feasible to visit as day trips from Santiago. To me Pontevedra looks like a nicer option as there looks to be more to see than A Coruna, but as our we are interested in seeing Roman sites I am wondering if Hercules Tower in A Coruna is a "must see".
By the time we get to Santiago de Compostela we will have visited Merida, Segovia and Lugo in Spain and we will also be going to Lisbon and Evora in Portugal. We have seen Roman ruins in Tarragona and Barcelona on a previous trip.
We will not have a car and would be using train or bus to make the trips. Time-wise we don't have time to do both as we will only be in Santiago de Compostela for three nights having arrived from Lugo and then heading into Portugal.