This monolith is located next to the river, near the Santa María bridge. According to the legend, it was in this place where El Cid spent his first night in exile camping with his supporters after the King had prohibited locals from allowing him to stay in their houses. Written on the stone we can read some verses from the poem Cantar del Mio Cid:

«MIO CID ROY DIAZ, EL QVE EN BVENA ORA CINXO ESPADA. =POSO EN LA GLERA QVANDO NOL COGE NADIE EN CASA. =DERREDOR DE VNA BVENA COMPAÑA» Poem: verses 58 to 60

«LA CARA DEL CABALLO TORNO A SANTA MARIA. = ALZO SV MANO DIESTRA. LA CARA SE SANTIGUA =»A TI TE LO GRADESCO DIOS, OVE CIELO E TIERRA GVIAS. =VALAMEN TVS VERTVDES. GLORIOSA SANTA MARIA». Verses 215 to 218.

This is where the legendary event of El Cid’s chest took place.