In Peter's writings we find that the 1st heaven and earth were destroyed by the Flood:
2 Pet 3:5-7
5 For this they willingly are ignorant of, that by the word of God the heavens were of old, and the earth standing out of the water and in the water:
6 Whereby the world that then was, being overflowed with water, perished:
7 But the heavens and the earth, which are now, by the same word are kept in store, reserved unto fire against the day of judgment and perdition of ungodly men.

The result is the world we now live in. This is concluded to be the 2nd heaven and earth. This present age, or "heaven and earth" will be destroyed in the fire of "the day of judgment".