The locality is freely accessible from the west; two comfortable paths ascend the two castle mounds from the information board by the road. The owners of the weekend homes do not keep their properties closed to the public. In addition to the somewhat meditative pond, the romantic atmosphere of the site is augmented by a picturesque Jewish cemetery, which can be easily reached by following the path along the elevated outer surroundings of the castle. The ruins of Boršengrýn Castle are situated in the vicinity of the village of Úbočí, approximately five kilometres northwest of Lázně Kynžvart.
Boršengrýn is arranged into two sections – the castle motte (hill) and the outer surroundings currently separated by an asphalt road which necessitated the deepening and widening of the original shallow rock-cut moat. Another well-preserved moat and rampart separates the outer surroundings from the continuing summit crest. The security of the castle was strengthened by two ponds under the castle motte, of which only one has been preserved to this day.
The village of Úbočí with its stronghold belonged to the Leuchtenberg feoffs in the Middle Ages. In the 1350s, the stronghold was in the possession of Engelhart of Kynžvart who permanently settled there after losing Kynžvart Castle in 1347. In 1373, the village and the stronghold were purchased by Boreš of Osek (from Rýzmburk) who, after acquiring the Emperor's permission in 1374, built a new castle on the site – Boršengrýn Castle. In 1392, his son sold the Kynžvart demesne to the King's Vice-Chamberlain, Sigmund Huller, who exchanged it with Hynčík Pluh of Rabštejn for Orlík Castle upon the Vltava River (in 1395). The importance of Boršengrýn Castle diminished with the renewal of Kynžvart Castle during the reign of King Václav IV (also denoted as Wenceslas IV of Bohemia) after 1398. When the castle was acquired by the Lords of Plavno in the early 15th century, it was often pledged by the family and thus, its owners changed quite frequently. Jindřich of Plavno managed to buy the castle back in 1452. Nonetheless, following a harsh conflict with the town of Cheb, the Cheb army commanded by Otto of Sparneck and Konrad of Reitenbach besieged the castle. The besieged castle was won by the army eight days later with the aid of cannons and it was burnt and destroyed. It was never rebuilt and remained in ruins. By and by, the remnants of the stone walls were disassembled for the building of a farmstead situated not far from the castle motte.
Boršengrýn Castle used to stand at the western edge of the village where a high hill separated by a fault from a more extensive elevated knoll rises above the village. The castle layout was clarified by archaeological research carried out on site by Pavel Šebesta from the Cheb Museum between 1982 and 1984. The inner ward of the castle used to stand on the motte. A rectangular 10 x 10 metre tower (the keep) stood at its front above the moat. The keep was surrounded by a barbican enclosed by a 1.6-metre thick outer barrier. The castle gateway was probably located near the south corner of the castle. A large, 8.5-metre wide oblong building was built on the other side of the massive keep. The remaining castle grounds were situated further north where the archaeological research found evidence of additional buildings. The inner surroundings and the south outer surroundings were separated by a ditch originally furnished with a drawbridge. Entry to the outer surroundings was via a path leading to the southwest corner. An unknown type of peripheral fortification stood above the ditch that separated it from the summit crest in the south. The fortification was adjoined by an oblong structure with several rooms that may have served for farming purposes.
The ill fate of the castle was sealed by the insensitive building of recreational weekend homes on the site of the outer and inner surroundings. As a result, only unclear traces of the original castle structures can be seen today.