Cargar GridView con listas genericas

Class1.cs

using System;
using System.Collections.Generic;
using System.Linq;
using System.Web;

public class Listas
{
    public class Columnas
    {
        public string Col1 { get; set; }
        public string Col2 { get; set; }
        public string Col3 { get; set; }
    }

    public static List<Columnas> MiMetodo()
    {
        List<Columnas> lista = new List<Columnas>();
        lista.Add(new Columnas 
             { 
                Col1="1racosa", 
                Col2="2dacosa", 
                Col3="3racosa"
             });
        return lista;
    }
}

default.aspx.cs

GridView1.DataSource = Listas.MiMetodo();
GridView1.DataBind();

default.aspx

<asp:GridView ID="GridView1" runat="server" AutoGenerateColumns="False">
    <Columns>
        <asp:BoundField DataField="Col1" HeaderText="Col1" />
        <asp:BoundField DataField="Col2" HeaderText="Col2" />
        <asp:BoundField DataField="Col3" HeaderText="Col3" />
    </Columns>
</asp:GridView>