grid defined rows auto cololumns
#container {
display: grid;
grid-template-rows: 1fr 1fr 1fr; //3 rows
grid-auto-flow: column;
}
<div id="container">
<div>1</div>
<div>2</div>
<div>3</div>
<div>4</div>
<div>5</div>
<div>6</div>
<div>7</div>
<div>8</div>
<div>9</div>
</div>