The National Museum of Scotland is both free and great fun, the 4 person track bike is certainly a winner, and the science bit with Dolly the Sheep, the mini rocket you can lauch, the F1 simulator and the robot that will spell your name were personal favories
If you're in need of a laugh, go to the Tartan Weaving Mill & Exhibition, its so bad it's funny.
The Castle is good but expensive.
The National Museum of Scotland is both free and great fun, the 4 person track bike is certainly a winner, and the science bit with Dolly the Sheep, the mini rocket you can lauch, the F1 simulator and the robot that will spell your name were personal favories
The Museum on the Mound was good too.
Pubwise, The Halfway House was good last time I was there