Espinosa de los Monteros is a proper town with services and character. The name refers to the Monteros de Espinosa, a royal bodyguard corps established in the 10th century — the oldest in Europe — whose descendants still serve the Spanish crown ceremonially. The town has a handsome plaza mayor with lively bars and occasional folk dancing.
Hostal Sancho Garcia, recommended by Adolfo, faces the plaza mayor — ask for a room with a balcony for front-row seats to any evening entertainment.
Espinosa has supermarkets, cafes, restaurants, a pharmacy, and an ATM.
The day's walking from Espinosa is almost entirely off-road, through small villages and a beautiful natural area. There's one ascent of about 200 m to a great viewpoint, and a stretch on the Via Verde — an abandoned railway from the never-completed Santander-Mediterranean line, begun in 1879 and halted definitively in 1959.
A shorter alternative through the forest splits at Entrambosrios and is marked.