Moridunum was a Roman fort and town located in the Roman Province of Britannia. The site is now the modern-day town of Carmarthen in Wales. The settlement originally started as a fortress that is believed to have been founded around 75 AD. The fortress was then converted into town in 120 AD.
The only above ground Roman remains in the town is the amphitheatre. The amphitheatre is one of only seven surviving Roman amphitheatres in the UK. The site was excavated in 1968.