An adult lion is not as strong as an adult elephant; although lions have more speed and agility, which gives them an advantage as apex predators. Elephants are the largest and strongest land animal.
Both lions and elephants have extraordinary strength, but elephants have enough physical power to knock down trees with their trunks and even push railway cars off of their tracks.
While lions are known for their strength as well, they also have an ability to run at over 30 miles per hour. A lion can bring down prey such as a gazelle or small water buffalo alone, but often lions hunt in packs in order to have an advantage.
Lions are known to attack elephants when other prey is scare. Sick elephants or babies make the easiest targets, but even large elephants can be attacked by a group of lions if conditions call for it.