From airports:

From Roissy - Charles de Gaulle

•    Take the train to Reims centre (about 1 hour from Roissy – Charles de Gaulle)

From train stations:

•    Champagne Ardenne TGV, this train station is at about 7 km from the ICP. Then, take the train to Reims Centre.

•    Reims Centre, take the bus line 2 or line 6 and get off at « Conservatoire ». 
You can also walk : cross the park in front of the station, then take « Rue Thiers » and « Rue Talleyrand ». Go foward until to cross « Rue Lieutenant Herduin », take it on the left (20 min walking from Gare de Reims).