Aberystwyth Marina sits within the town's harbour where the Afon Rheidol meets Cardigan Bay on the west coast of Wales. The marina is dredged to approximately 2. 3 metres, though silt carried down from the river can accumulate over time.

Visiting boats remain afloat at all states of the tide within the marina basin. Approaching by sea, the entrance is narrow with a sharp 90-degree port turn inside the Wooden Jetty head.

A bar lies immediately outside the Stone Pier head; at low water springs, depth on the bar is around 0. 7 metres on the leading line. Boats drawing 2. 0 metres are advised to enter no more than 2. 0 hours before and 2.

5 hours after high water in calm conditions, while those drawing up to 1. 0 metre have a wider window of 3. 0 hours before and 3. 5 hours after high water. The marina monitors VHF channel 14, with initial contact on channel 16.