Helmsley Castle was first built in 1120 and rebuilt in stone later in
the 12th century. The stone castle had a curtain wall with round corner
towers and two entrances, one in the south-east below a strong square
tower and one in the north in a gatehouse with paired round towers. There
was also two great towers, the East Tower and West Tower.
Late in the 13th century another storey was added to the East Tower,
the south barbican was strengthened and a new Hall added to the side of
the West Tower.
In the 1560's the West Tower and Hall were converted into a fine
Tudor house.
In 1644, a parliamentary force laid siege to the royalist
held castle for three months. The garrison eventually surrendered and
much of the castle's walls, gates and the eastern half of the East Tower
were destroyed to prevent any further threat. The Tudor house was left
intact, but was abandoned in the early 18th century in favour of a new
house in the adjacent Duncombe Park.