Aviemore is the most popular gateway to the Cairngorms National Park which comprises the largest mountain massif in Britain. From the Highland town the great rounded mountains can be seen which form an extensive plateau that is arctic in character. It is home to many nationally and internationally important plants and animals and hosts a thriving reintroduced reindeer herd. The Cairngorm mountains are at their most impressive in the winter when large snow cornices can form on the deep corries.