A sea mark is an aid to navigation, usually to warn of a hazard and sometimes to mark a channel. They can feature a light, an easily seen prominence, a foghorn or be painted in a prominent colour. This sea mark in the form of an obelisk is at the tip of Portland Bill, an island that projects into the English Channel. The initials T.H. denote Trinity House who had it erected here in 1844 as an addition to two old lighthouses that were later replaced.
photo © T. Boughen Camera: Nikon Z 5
