LEGO 6090 Royal Knight's Castle is a vintage Castle set from 1995 valued at $3,443 for new and sealed sets, up 3525% from an original retail price of $94.99. Annual appreciation has averaged 9.20% since release. Used copies are valued between $327 and $420 depending on condition. Signals for the set are mixed, with thinning listings set against a value that has slipped lately.
LEGO 6090 Royal Knight's Castle is a Castle/Royal Knights set released in 1995, containing 764 pieces and 11 minifigures. The large fortress sits on a 32 x 48 x 6 raised baseplate with a central pit and stone pattern and includes dual gates, battlements, and three horses. Characters include six guards, two knights, a glow-in-the-dark ghost, a skeleton, and King Richard, whose horse barding, cape, and the large Royal Knights flag are exclusive elements.
Features include a throne-room trapdoor, a dungeon beneath the ramp, a secret passage under the walkway, a wall-mounted catapult, and a flip-up yard plate concealing the skeleton. Known as King Saxondale Castle in the United Kingdom, the set’s box also highlights several alternate builds, including a brick-built dragon.
New and sealed, Royal Knight's Castle is worth about $3,443 today. It has averaged 9.2% a year since it retired, and our forecast has it near $3,638 next year and $4,526 in five. The average used price is $350 for those in good overall condition. The 11 included minifigs account for approximately 13% of the set's total value. New and sealed listings currently range from $2,609 to $3,386.