Many did, many didn't. It often came down to what culture was building the castle, and in what time period.
Most had a dungeon of sort below them, and these could have passages.
A particularly common time for them to have secret passages was in Spain during the inquisition, where there was a "lot of torturing to do" and secret passages would have aided in secrecy of otherwise forbidden/cruel acts.
Medieval castles.
Medieval castles evolved because the old Motte and Bailey castles where easier to set alight and where not very strong, so they made stone castles to improve defence.
Medieval castles had no steam room.
This big.
Yes, it's true. In medieval castles spiral staircases ascended clockwise.
Medieval castles.
There is nothing different between todays castles and medieval time castles. Today's castles were built in medieval times.
The welsh medieval castles were big and gray.
Medieval times
in the late medieval period many medieval castles did have a primitive type of cannon.
Castles were invented in medieval times.
There are no genuine medieval castles in the USA, because the Americas were not discovered until after the medieval period had ended. There are the "fairytale" Disney castles and some modern attempts at reconstructing medieval castles, but no genuine ones.
Who is most important in medieval history - kings and emperors. Where do they live - in castles.
Motte and bailey castles, Stone keep castles and Concentric castles
Medieval castles evolved because the old Motte and Bailey castles where easier to set alight and where not very strong, so they made stone castles to improve defence.
medieval Europe
Life