Lake Valor
In the anime
Lake Valor was the location of the Wallace Cup tournament and the Sinnoh Grand Festival. Like the games, the Hotel Grand Lake and Seven Stars Restaurant were located nearby, and Ash, Dawn, Brock, and May all battled at the restaurant.
In Pruning a Passel of Pals!,Ash decides to go for a walk with Pikachu after falling from his bed. At the lake,he had a brief encounter with the projected soul of Azelf,similar to Dawn's and Brock's encounter with Mesprit and Uxie respectively.
In The Needs of the Three!, it was explained that Lake Valor, as well as all three of Sinnoh's lakes, are the entrances to another world where the lake guardians live, and they do not actually live in the lakes themselves.
In the same episode, Pokémon Hunter J dropped the Galactic Bomb, bringing out Azelf from its home and drawing out Mesprit and Uxie when their comrade was captured. She was challenged by Gary, who was working with Professor Rowan, but Saturn's Toxicroak quickly beat his Umbreon and Electivire.
