During the winter and spring nights, fog often forms in Estonian maritime waters. In case of poor visibility or fog, the seafarers were notified of the danger and aided in navigation by fog signals. Then the crew of the lighthouse started to ring a bell at certain intervals. In later years, a siren was installed. The Suurupi Rear Lighthouse controlled the Front Lighthouse and the Ninamaa siren station, which was on the Ninamaa cape, 1500 m from the Rear Lighthouse, and where a whole complex of a siren and service buildings were built in 1898. Today, the siren building, dwelling, sauna and a tilted mast of the nautophone remain of the siren complex. Every year, the stormy sea gnaws away at the Ninamaa cape and the historic complex faces impending destruction.
On the tip of Cape Ninamaa, there was a fog siren, and a ‘private pilot station’ was nearby. This information is from 1927.