The home of the relatively toothless 732-member European Parliament , used just 12 times a year for four-day 'part-sessions' (plenary sessions), is 2.5km northeast of the cathedral. When it's in session (dates are available from the tourist office or on the website - click 'Activities' and then 'Parliament's Calendar'), you can sit in on debates for up to one hour; it's first-come first-served (bring ID) and no reservations are possible.

The rest of the time the building is inaccessible because of strict post-9/11 security measures.