The regular service from Carmarthen is the 166 bus connecting Carmarthen Train Station, Cross Hands, Pontyberem and various other places to National Botanic Gardens and drops off within the Gardens car park. 166 bus timetable. Visitors to the Garden who use the local bus services will be entitled to half price entry on presentation of their bus ticket.
Alternatively, Traveline could help you with your public transport queries. You can visit their website www.traveline.info, call them on 0871 200 22 33, or text 84268.