Dense forests and tall mountains made overland travel difficult, but long coastlines and numerous rivers, lakes, and fjords provided a viable alternative.
Norway is famous for its fjords, and you don't have to travel far to see one. You can take a boat from the harbor, and in less than an hour you'll be sailing down the Oslo Fjord.
When glaciers melt along the coast, rounded depressions flood with a mix of seawater and glacial meltwater, creating fertile ecosystems called fjord estuaries.
This fjord is amazing. It's very quiet and calm. It has a lot of wild animals. Sometimes you see foxes running around, sometimes there are whales, dolphins. And yeah, it's just a great place to recharge and meditate.
It used to be common in springtime to see herds swimming across a fjord to reach the lush grass of an untouched island, the herders and their dogs following in kayaks or rowing boats.
Golfo Dulce is one of the only tropical fjords in the world, and its warm waters provide the perfect breeding and nursing ground for a host of extraordinary marine animals.
The coast is dominated by jagged fjords that zigzag around in every direction, and then there's all the seemingly endless amount of islands to consider as well.
Scientists say a melting glacier collapsed under the weight of the rock face above it, sending enough rock and ice to fill 10,000 Olympic-sized swimming pools into the fjord below.