Maybe my Reddit is bugged, but it says there are 4 comments and I can only see one. So I apologise is I am just repeating other comments because I cannot see them.

But to answer your question, no. There were not.

The closest thing we had to castles prior to 1066 were either Walled Towns (London, for instance), or HillForts.

The Hill Forts (aka Motte & Bailey), were constructed primarily by the Romans prior to their departure in around 410AD. Whilst the Saxons did 'upgrade'/build more Hill Forts, it wasn't until Alfred's Burgal Hideage (sp? On phone so cant check right now) that we see a major effort to increase the defnsive capabilities of them.

Such defensive towns in Wessex may have resembled wooden 'Castles', but they were still just forts.

One of the reasons William's Army was able to take England so easily was because there were no castles about.

What would you define as castle? Any fortified location or a defensive structure? If we look away from hill forts and fortified settlements, I'd say the Saxon Shore forts the Romans built in later Imperial years would suffice. They were intended to defend Britain against Saxon naval raids and were concentrated along the coast of east and south-east England. The castle of Portchester, near Portsmouth was built on the pre-existing Roman castle walls there.