According to Genesis, what was built after Noah left the Ark?

According to Genesis, Noah built an altar after leaving the Ark.

Genesis 8:20 says that Noah built an altar to the LORD after the floodwaters receded and he came out of the ark. He then offered burnt offerings from animals and birds described in the passage as clean. This is the first altar specifically associated with Noah in the flood narrative.

The scene marks a transition from survival to worship and thanksgiving. It is followed by the covenant described in Genesis 9, including the rainbow as its sign. The text therefore links the altar, the divine promise, and the restoration of life after the flood.

The answer is not a tower or permanent settlement. Genesis says that the animals leave the ark, Noah builds an altar, and God establishes the covenant. Later biblical stories include many other altars and major structures, but the immediate construction after Noah’s departure is the altar.