Nabelkalns or border hill is a state-protected archaeological monument. The hill, shrouded in myths and legends, between two counties by the Vecnābele River, also called Lūžupi or Nabeļupi, marks the historical border between the lands of the Livonian Order and the Courland diocese, and later, from 1680, between the papal estate of Baron Behr and the Ventspils crown estate. This object attracted the attention of historians already in the 19th century. Augusts Bīlenšteins recorded it in 1869.
Nabel Hill is located in Tārgale parish, Ventspils region, on the right side of the former Lūžņa – Miķeļtornis narrow-gauge railway line, on the property of “Olmaņu mežs”, which is managed by the Latvian State Forests. The hill is located approximately 0,3 km southwest of the “Vētri” house and approximately 120 m south of the former railway line tracks. It is a lonely hill with very steep, approximately 10 m high sides, the top of the hill was excavated in ancient times. The Vecnābele River flows along the southeastern, southern and southwestern sides of the hill. According to archives, excavations have been carried out on the hill several times in the 20th century; one ditch has been excavated at the top of the hill. Now the hill is difficult to see, overgrown, trees have fallen on it; they are also visible at the foot of the hill.