It is on the Vale of Glamorgan Line 2+3⁄4 miles (4.4 km) south of Cardiff Central on the way to Barry Island and Bridgend.

The current platforms were constructed in 1888, but until 1968 Cogan had two additional and separate platforms on the other side of the main Windsor Road, opened twenty years earlier in 1878[clarification needed] on the Penarth and Sully branch line, which extended from the Cogan Junction points around the coastline through Lavernock and Sully to where it rejoined the main line at Cadoxton.

Dingle Road Halt and Penarth station remain open, but the two platforms at Cogan were closed when the line was reduced to a single-track spur.

Most of the station buildings still stand but have been used by several private businesses including a shooting range, a garden centre, a second-hand car lot, and a marine chandlers.

The area originally covered by the Cogan and Penarth dock's railway sidings and engine maintenance sheds now contains a large Tesco supermarket.