The Greater Ring or Intermediate Ring in Brussels, Belgium (French: Moyenne Ceinture, Dutch: Middenring) is a set of roads in the shape of a ring, intermediate between the small ring and the main Brussels ring motorway. The greater part of this set of roads is numbered R21 and is about 30 km long, compared to 8 km for the small ring and 80 km for the main ring.
It crosses two highways (A12 and E40-east) and offers a connection to the E40-west at Basilique/Basiliek via Avenue Charles Quint/Keizer Karellaan, to the A12 at Gros Tilleul/Dikke Linde, to the E19-north and A201 at Leopold III via Boulevard Léopold III/Leopold III-laan, to the E40-east at Reyers, to the E411 at Arsena(a)l via Boulevard du Triomphe/Triomflaan and to the E19-south at Paepsem via Boulevard Industriel/Industrielaan.
This road passes through tunnels (Boileau tunnel, Montgomery tunnel, Georges Henri tunnel), on bridges and viaducts (e.g. Diamant viaduct, Teichmann bridge and Van Praet bridge) and under bridges and viaducts (e.g. Luttre bridge). Among those bridges, 7 are used to cross railroads and 2 are used to cross the Brussels-Scheldt Maritime Canal. Tunnels and the Diamant viaduct are used to avoid crossroads. The greater ring runs along many parks: the Royal Domain, the Josaphat park, the Forest park, the Astrid park, the Scheutbos park, the Elisabeth park, the Jeugdpark and the Laeken park. It also crosses the Bois de la Cambre.
The road goes through 14 municipalities out of the 19 which form the Brussels Capital Region: City of Brussels, Schaerbeek, Woluwe-Saint-Lambert, Woluwe-Saint-Pierre, Etterbeek, Ixelles, Uccle, Forest, Saint-Gilles (only when riding counterclockwise), Anderlecht, Sint-Jans-Molenbeek, Koekelberg, Ganshoren (only when riding counterclockwise) and Jette.