One of Edward I's ring of castles around Wales to suppress the Welsh, the castle cost £15,000 to construct.
It is evry little boy's vison of what a mdeiaeval castle should be, with lots of towers and ramparts and stairs.
Richard II used Conwy as his base in 1399 for negotiations with the future Henry IV before moving to Flint
http://en.wikipedia.org/wiki/Conwy_Castle