Ateneum is one of the three galleries that make up the Finnish National Gallery – it’s right in the heart of Helsinki and carries many 19th century works. They’re got great access to their materials online and in English and you can enjoy it several ways (I’m tempted to shell out for one of the live virtual guided tours). You can walk through some of the galleries on Google, including clicking on paintings for HD views and more information, or a pared down version here:

They also have some nice overview written tours, and short documentaries on some of pieces:

Much of the art at Ateneum seems to spring from the creation of Finnish national identity in the 19th century that led to eventual independence from Russia – there’s very much a focus on the Finnish countryside and interpretations of the Kalevala, such as the slave Kullervo swearing revenge after breaking his father’s knife on a stone baked into bread: