Ledesma still has most of the granite wall which historically has surrounded the town. A large part of what is still standing was built in times of Fernando II of Leon, in the 12th century, but in the 15th century several parts of it were rebuilt with well-carved masonry. Many stone mason marks can be seen among these stones. Out of the eight doors it once had, the only one that is still preserved is the one called Puerta de los Mártires, de San Nicolás or Caldereros (Martyrs’, San Nicolás or Boilermakers’ door). Formed by two camber arches, it is flanked on either side by two cylinder towers.
The bailey of this castle-fortress was built on the south-west end of the walled area between the 13th and 14th centuries. Set on an irregular trapezoidal plan, it has two doors: one on the north, which features the town’s coat of arms, and one on the south, flanked by two large towers.References:
Frösöstenen is the northern-most raised runestone in the world and Jämtland's only runestone. It originally stood at the tip of ferry terminal on the sound between the island of Frösön and Östersund. The stone dates to between 1030 and 1050. It has now been relocated to the lawn in front of the local county seat due to the construction of a new bridge, between 1969 and 1971, on the original site.
Frösö runestone inscription means: Austmaðr, Guðfastr's son, had this stone raised and this bridge built and Christianized Jämtland. Ásbjörn built the bridge. Trjónn and Steinn carved these runes.