[Django]-NoReverseMatch in Django 1.10

You should use admin namespace, like written in the docs. You could also look on other admin urls in that namespace.

{% url 'admin:index' %}

Use admin:index if you want to have an url to /admin/ site.
If you install django-extensions you can use ./manage.py show_urls to get the list of urls for your app

Set admin url in your project urls.py, same folder as your settings.py

Url(r'^admin/', admin.site.urls),

Then call it in your template:

<a href="{% url 'admin:index' %} > link </a>