The invention concerns a wind power installation, in particular a wind power installation for the offshore region. The object of the invention is to overcome the previous difficulties and avoid disadvantages, in particular also to allow people to be constantly landed on the installation even when weather is so bad that flying by means of helicopters is no longer possible. A wind power installation comprising an entry and a space in the interior of the wind power installation, in which electrical or electronic components of the wind power installation are disposed, characterized in that provided between the entry of the wind power installation and the internal space in which the electronic components are disposed is a lock which prevents water that enters through the entry and/or salt-bearing or moist air which enters when the entry is opened from passing into the internal space of the installation.