The main sea front in Aberystwyth (from the section before the main area to the statue on the hill) is part of a "special charter" from years ago where the land was given to the people of Aberystwyth so is not under council control, there is a section maybe a quarter of a mile long which has about 30 car parking spaces on the side of the road (think any sea front where you park facing the sea) this road is used by campers to stop overnight or longer and you can't get moved on, when i went last year there was a bay there who had done 3 nights and plenty of other boring vans.... The downsides are obviously you're parked on a road, there is always the option of drunks walking past your bus overnight shouting or i guess banging your windows, there is a toilet block nearby but typically it's only open from dawn to dusk but i guess you can stock up with bottled water for the night and fill them later..... I'm sorry i don't know how to do co-ordinates etc but with the pictures below you'd be pretty dumb to not realise you're parked in the right place. This picture shows the limit to the free area, once past this you're into the main town and have to pay. This picture shows the old ruins which run above the free area. This is me and Malc parked in the area showing how close you park to the road, the flagstones show the path just past them is the sea. This picture shows a different view back to the start of the free area, the bay is the one i mentioned above and who told me the free camping story (i have since had this backed up by other people including my friend who lives in Aber) Hopefully someone will add the details of co-ordinates but really you don't need them it is a simple place to find.