A Speed Shrine is a terrain feature found on the Crystal Scar. The champions that are specifically affected by the buff are dependent upon the map the shrine is located.
There are three or four Speed Shrines on the Crystal Scar and the shrines are perpetual, buffing any champion that passes over them regardless of team alignment with a 30% movement speed boost that decays over 10 seconds. Their locations are placed such that their use can equalize travel time between any two capture points, whether a champion is moving from the Boneyard in the bottom left to the Refinery in the upper right, or just across to an adjacent point.
Speed shrines allow players to have significantly more strategic options whether they are confronted with a stalemate, or are simply looking to keep an opponent on their toes by launching a timed attack at a cross-map objective.