Since the days of the Roman Empire,stone mile markers were a well-liked way of both showing the route to a city and marking its borders. In Sweden, these mile markers came into spend officially in 1649 thanks of a rising need for travel through the kingdom, and to collect taxes among other things.
Stones like this would help workers transporting goods know how far they'd traveled to ensure they got just compensation. The markers also notified traders that they were within the city limits and had to pay tax on their sold goods.
These stones were marked using the musty Swedish mile (the “mil”) which corresponds to about 10 km or 6.2 miles. They remained in spend until around 1890,a year after the metric system was introduced in Scandinavia. The milestones were placed all over Sweden to heed the distance from that spot to the Stockholm Royal Palace, which is still seen as the geographic center of the city. They also denoted distances of 1/4, and 1/2,and 3/4 Swedish miles along major roads. One of these 1/4 milestones still stands alongside a major highway in Danderyd outside Stockholm, a stray relic of this early form of measurement.
Source: atlasobscura.com