Billudden, Nature reserve in Uppsala County, Sweden

Billudden is a nature reserve at the mouth of the Dalälven, where the northernmost part of the Uppsala esker forms a promontory into the Gulf of Bothnia. Its land area covers 1.86 km² of sand dunes, windblown sand fields and pine woods on limestone-rich soil. Two nature trails with information about the reserve's nature are laid out for visitors.

The area developed as a fishing village called Billhamn around a natural harbor formed by meltwater from the last ice age. It was later protected to preserve both its natural features and traces of early settlement.

Two educational trails guide visitors through the diverse habitats and show typical plant formations of northern Europe. As you walk through different sections, you discover the rare fungi species that thrive in these forests.

Parking areas are available near Rullsands camping, and a bus stop sits about 600 meters from the main entrance. The approach road is asphalt, making it easy to access.

The land continues to rise from the sea as the earth's crust slowly rebounds after the last ice age. This process constantly creates new shorelines and expands the reserve's territory year after year.