When the townsfolk of Newark were ordered by Cromwell to destroy the castle, it is something of a relief for those with an interest in our heritage that they did not erase it completely. Newark Castle was an important stronghold for the Normans and, possibly, for much earlier settlers. During the course of several archaeological excavations, much evidence has been found to suggest that the site had been occupied for some 5000 years. Today, little of the Norman castle survives but certainly enough to visualise what a powerful and impressive sight it must have been in medieval times.

The ruins of Newark Castle still dominate the river view from the opposite banks of the Trent. A long curtain wall, incorporating a splendid Romanesque gatehouse, remains standing to almost its full height of 20 metres. Behind this western facade, very little of the original structure is visible and the site has mostly been laid out as a public park.

Newark Castle was owned by the Bishops of Lincoln for about 400 years but, not wanting to reside at the Bishop's Palace in Lincoln, it was the infamous Bishop Alexander who decided to make Newark his residence of choice. During the 1130s, Alexander 'the Magnificent' largely rebuilt and remodelled the existing castle at great expense, incorporating lots of ornately carved stonework and replacing timber palisades with massive stone curtain walls. He was responsible for giving access to the town by building the bridge over the river and, at the same time, improved the buildings in Newark.

During the 14th century further remodelling of Newark Castle took place, and a Watergate was created to provide a more convenient way for supplies to be delivered to the castle by river. Over the next three centuries, the castle gradually evolved from the practical, sturdy fortification to a stately country residence with all the modern conveniences of the time. Additional rooms were provided by inserting floors in the large open areas, more fireplaces were built, and window glass appeared in the openings. In fact, it was so appealing by the 17th century that King James I decided to stay at Newark Castle en route to London in 1603. His son, Charles I, is known to have stayed many times to enjoy the hospitality at the castle. They must have experienced a very different castle to that first visited by King John in 1205. The south west tower of the castle is remembered as 'King John's Tower' as legend suggests he died there in 1216, after returning from a successful campaign against the King of Scotland.

When Newark Castle reverted to Crown ownership following the Reformation, the now ruinous buildings fell into decay. Local people used it as a convenient quarry, collecting stone to carry away and build their own homes, and 'squatters' inhabited some of the more sheltered parts of the castle. By 1840 this 'slum' was cleared to make way for a cattle market but within a few years proposals were being considered to consolidate the site as an historic monument. In fact, this was the first site to be consolidated, at government expense.

Eventually, the Town Corporation landscaped the site and it was opened as a public park in 1889. Since that time, the surviving structure has been subject to continual repair and restoration, and is still maintained as a 'romantic' backdrop to public grounds.