Cardiff City Hall
While this imposing Edwardian building may not seem particularly mermaidy at first, look closer and you'll discover some marine themed details, from the ornate seashells on the facade, to Neptune himself and a bunch of beautiful merpeople perched near the top of the building.
The Natural History section of the Museum is home to an unexpected mermaid paradise, with a huge gallery covering all aspects of marine life, from collections of seashells to a whale skeleton. There are even exquisite models of rock pools. There is also an emphasis on preserving the ecology of the oceans, a cause close to any mermaid's heart. Incredibly beautiful and extremely educational, this is a must visit.
This beautiful park is intersected by the waters of the River Taff, and you can also spot this wonderful sculpture of an otter chasing fish.
Travelling from Bute Park to Cardiff Bay by Aquabus is a magical experience, with the gorgeous green waters of the Taff lapping against the sides of the boat. It's also a great way to see bits of Cardiff you wouldn't normally notice, and a chance to see water birds such as coots, moorhens and cormorants.
This huge expanse of shimmering water is breathtaking, and is surrounded by interesting buildings. You can take boat tours of the Bay, check out Mermaid Quay for shopping and eating, or simply stroll around taking in the many maritime details. Particular gems to look out for are the aquatic architecture of the Pierhead building, and the marine life carved into the walkway leading to the Norwegian Church.
Let me know if you visit any of the places on my list, and if you have any other mermaidy suggestions for things to do in Cardiff, please leave them in the comments!