Went to Legoland yesterday with our just turned 4 year old daughter and 6 year old son…great day out. We had grandparents with us so the 4 year old went on the more sedate rides with the grandparents whilst we took the 6 year old on the rollcoaster rides (110cm ride heights for rollcoasters iirc). 4 year old went down the rapids water ride (100cm ride height iirc) and loved it…which surprised us. I’d probably leave it until they are 3 years old to really enjoy it.
Not a cheap day but very good fun and Legoland is cleaner and better maintained that the Tussauds theme parks IMHO. Plus there’s Lego!!! So when everyone’s cream crackered you can stroll around the Lego city.
Only minor thing was the queue out the park: took us an hour to get out from the car park!
Off to Disneyland in a month and I’ll be interested to see how that compares. Paultons we really enjoyed and the kids were 3 and 5 when we last went.