Statement 1 states that Maharashtra State has the maximum share of national highways in terms of length in kilometers. This means that Maharashtra has the largest total length of national highways among all states in India. This statement is correct.

Statement 2 provides a reason for the maximum share of national highways in Maharashtra. It states that the nature of the terrain and the level of economic development play a role in this. This means that the geographic conditions and the level of economic activity in Maharashtra make it necessary to have a higher number of national highways. This statement is also correct.

Therefore, both statements 1 and 2 are correct. Maharashtra does have the maximum share of national highways, and this is due to the combination of its terrain and economic development.