All transport in the city (bus / train / metro) are handled by Ruter (ruter.no). A single-fare ticket costs 36 NOK, and a one-week pass costs 285 NOK. Stay in Majorstuen area to save on transport costs.
TIP! Save up on transport from the airport by using the regular train (NSB) instead of the express train Flytoget to save €10.
A handy map for Impro Neuf visitors, including Chateau Neuf (venue of all things festival) with surrounding restaurants and supermarkets, and places to visit in Oslo): LINK
TIP!: Dining out is quite costly in Oslo even for locals. During the festival, we can provide a shared Norwegian family-style lunch at local supermarket prices.