We depart from Leioa underground station and take Sabino Arana street to Lehendakari Agirre square.
From there, we turn off towards Doctor Luis Bilbao Street until we reach the footbridge over the Avanzada, next to the Municipal Conservatory.
We then go across it and along Mendibil Street we reach Mendibile Park, and from there, we take the Santsoena footpath that goes up to the University.

We enter the university grounds between the Faculties of Education and Fine Arts and soon find access to the Arboretum, from where we go down to the surroundings of the Lertutza reservoir.
We go up the geological trail to the east entrance and, first along the Via Apia and then along the Via Aemilia, we come out again at Santsoena.
To go down to Leioa, we use Universidad and Elexalde avenues, and to return to the underground, we cross the Boulevard and Sabino Arana avenue.
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