Welcome to the forum Fitta,
I fully expect a chap by the name of Jarama to provide a fully detailed answer to your Montjuic Park question. As I recall RolF Stommelin had a major accident there which resulted in the death of some spectators. The organisors were blamed because they failed to ensure that the safety barriers were installed correctly.
A section of Crystal Palace has recently been reopened by the BARC. They run a Sprint meeting in May.