At the place where the Kamenický stream meets the Sázava river, you can visit the mysterious ruins of the royal castle demolished Kostelec. The ruins are part of a nature reserve and are freely accessible.
The castle was probably founded in the last third of the 13th century by King Wenceslas II, but the first written mention dates back to 1342, when it was held in pawn by Oldřich Medek of Valdek. Although Charles IV bought back the castle in 1356, he soon pawned it again and it had several owners over time. The last of them was Kuneš Rozkoš of Dubá from 1443, who looted in the surrounding area, and therefore the castle was besieged in 1449. It withstood this siege, but a year later, on May 18, 1450, it was besieged again and five days later it was conquered by the army under the command of Zdeněk Konopišťský of Šternberk, who became its new owner. In 1456, serfdom was abolished and he fortified it as one of his military strongholds. Later, he became a leading figure of the anti-Poděbrady opposition, and therefore the royal army captured and destroyed the castle in 1467.
The Broch of Clickimin is a large and well preserved, though somewhat restored broch near Lerwick. Originally built on an island in Clickimin Loch (now increased in size by silting and drainage), it was approached by a stone causeway. The water-level in the loch was reduced in 1874, leaving the broch high and dry. The broch is situated within a walled enclosure and, unusually for brochs, features a large 'blockhouse' between the opening in the enclosure and the broch itself. Another unusual feature is a stone slab featuring sculptured footprints, located in the causeway which approached the site. Situated across the loch is the Clickimin Leisure Centre.