test.html

<table border="1px solid">
    <thead>
    <tr>
        <th>Dates</th>
        <th>Latitude</th>
        <th>Longitude</th>
    </tr>
    </thead>

    <tbody>
    <tr>
        {% for each in output %}
            <td>
                <table>
                    {% for data in each %}
                        <tr>
                            <td>
                                {{ data }}
                            </td>
                        </tr>
                    {% endfor %}
                </table>
            </td>
        {% endfor %}
    </tr>
    </tbody>
</table>

views.py

def test(request):
    s = ''
    s = ('dates,lat,long', ['date1', 'date2', 'date3'], [4, 5, 6], [7, 8, 9])
    data = {
        "output": s[1:len(s)] # Here we are slicing the output, since s[0] will mess up the HTML
    }
    return render(request, 'test.html', context=data)