Keskiniemi Beacon Tower is the oldest daymark still erect on the north shore of the island. The daymark was designed by Albin Stjerncreutz and built in 1858 to safeguard seafarers from sandbanks stretching from Keskiniemi northwards. The wooden tower has a six-metre high square base with a square pyramidical top. The tower also has a wooden top ornament. The structure measures 18,9 meters high from the ground. The beacon tower has a great culture historical value. A modern Keskiniemi sector light has been erected alongside the tower.
A trail leads from Keskiniemi to the daymark. It is a short walk away from the Sunijärvi hiking trail.