The Cuevas de Viera tumulus was constructed ca. 3800 b.c.e., much earlier than the nearby Cueva de Romeral (1800 b.c.e.). It is oriented about due east, 95 degrees. This reconstructed forecourt (completed in May, 2006) was built with new stones up to the original entrance. Near the entry are several orthostats, including five with cupmarks (all to the right) and an entry stone that was carved with a rectangular opening. Passing under the large lintel capstone, one encounters a 24 meter long passage. (See next frame) Another passage grave directly adjacent, Cueva de Menga, has a massive interior chamber.