After Rod Reiss turns himself into an enormous Titan, he slowly makes his way towards the Orvud District. Under Erwin Smith's orders the military is not to evacuate the citizens. He and Hange explain that if the residents of the District were to retreat further into Wall Sina, Rod Reiss's abnormal Titan would be drawn to the high population density in Mitras. Erwin acknowledges, however, that steps must be taken to protect the residents of the district. Therefore, the Garrison agree to have the citizens participate in an emergency evacuation "drill" so the populace will be ready to leave at a moments notice, a plan they put into effect at dawn.
There seem to be some inconsistencies in Orvud District's architecture. In episode 45, Orvud looked like a Wall Sina district and a city mainly inhabited by high-class citizens, but in episode 46, the city looked more like a district from Wall Rose or Wall Maria. "Orvud" is an Estonian word which means "orphans." According to Erwin Smith, the Garrison of this district are less effective than the Garrison of Wall Rose, because they are not used to fighting Titans. At the strategy meeting before facing Rod Reiss's Titan, the Garrison Regiment reports the Titan is approaching from the southwest. However, given the diagram of Orvud's location compared to the Titan and Mitras, this would only be possible if Orvud was in the south section of Wall Sina, where Ehrmich District is located.
Story: After Rod Reiss turns himself into an enormous Titan, he slowly makes his way towards the Orvud District. Under Erwin Smith's orders the military is not to evacuate the citizens. He and Hange explain that if the residents of the District were to retreat further into Wall Sina, Rod Reiss's abnormal Titan would be drawn to the high population density in Mitras.
Trivia: There seem to be some inconsistencies in Orvud District's architecture. In episode 45, Orvud looked like a Wall Sina district and a city mainly inhabited by high-class citizens, but in episode 46, the city looked more like a district from Wall Rose or Wall Maria. " According to Erwin Smith, the Garrison of this district are less effective than the Garrison of Wall Rose, because they are not used to fighting Titans.
Source: Orvud District (Anime), available under CC BY-SA 3.0.