Main Stadium

The  (referred to as the Olympic Stadium in the Wii version of the game), is a location in both versions of Mario & Sonic at the London 2012 Olympic Games. The stadium appears as the venue for all of the Athletics Events in the Wii version game, and all athletics events except for Marathon and 20km Race Walk in the Nintendo 3DS version. In the Wii version, as well as appearing as the venue for the Athletics events, the stadium also appears in the game's opening, as well as serving as the background of the single match mode and records menus. In the Nintendo 3DS version, the stadium serves a much larger role. Unlike the Wii version, where the awards ceremonies take place in the events' respective venues, the ceremonies all instead take place in the Main Stadium at night, and it also appears as the background for the game's main menu. The all of the box at for Nintendo 3DS version of the game except for the British one also feature the stadium in the background.

The Main Stadium also appears as one of the locations visited in the 3DS game's Story Mode. It first appears in The Night Before, where several Toads and Omochao are preparing the stadium for the Olympic Games' opening ceremony when the blue Phantasmal Fog first settles, scaring away most of the organizers. Toad is separated from Omochao and scared by a pair of Mario and Sonic Fog Imposters, which is observed by Bowser and Dr. Eggman from his lab in Big Ben. The episode Stadium Blues takes place in the Main Stadium the next day, when Toad encounters Mario and Luigi and tells them what happened the previous night, before they defeat a pair of Sonic and Tails Fog Imposters and go on to investigate the fog further after receiving some more information from Omochao. In Foggy Foes, the group find Dry Bones and Dry Bowser in the stadium protecting a Fog machine, and after defeating them destroy the fog machine, clearing the fog away and causing Dry Bones and Dry Bowser to leave. After noticing fog at Hyde Park, Mario, Luigi and Toad head off while Omochao remains at the stadium. In Clear Skies Again, the groups that had split off to clear up the fog around London meet back up at the Main Stadium and tell each other how they got on, celebrating the clear skies and deciding to prepare for the opening ceremony to go ahead. In A Rainbow In Fog, the rainbow colored Phantasmal Fog appears at the stadium, producing Fog Imposters of Mario, Luigi, Sonic and Tails that attack Cream and Cheese. Mario, Luigi, Sonic and Tails save them from the Fog Imposters, and then leave the stadium for Stonehenge along with Toad and Omega after he regains some more of his memory. Omochao, Cream and Cheese stay behind and provide Toad with a walkie talkie to stay in contact. Toad and Omega decide to head back to the Main Stadium for safety in The Promise to Toad, and call the group in Big Ben from there in The Grand Showdown, telling them that they alonng with Omochao, Charmy and Espio cleared away the fog from the Main Stadium and around the rest of London with help from the other groups. Once Bowser and Dr. Eggman are defeated, Toad calls again from the Main Stadium, telling them that they can register for the games by coming to the Main Stadium, and at the end of the episode the opening ceremony is held there. The Main Stadium also appears as the setting of the bonus episode Junior Triumphant!, where Bowser Jr. and Goomba arrive and watch Metal Sonic train with Dr. Eggman. Bowser Jr. convinces Dr. Eggman to let him challenge Metal Sonic, which he agrees to, and after winning gets Dr. Eggman to tell Bowser how well Bowser Jr. did. The final episode that the Main Stadium appears in is Stadium Blues, in which Magikoopa tricks Donkey Kong into challenging Bowser using a pile of Bananas and a Thwomp. Bowser arrives with Lakitu and Goomba and defeats Donkey Kong, before heading to ExCeL London, while Magikoopa and Donkey Kong head off to find some real bananas.