The Spanish Peninsula also possesses rock-hewn tombs. At Palmella, near
Lisbon, is a circular example about 12 feet in diameter preceded by a
bell-shaped passage which slopes slightly downwards. Another circular
chamber in the same group has a much longer passage, which bulges out
into two small rounded antechambers. These tombs have been excavated and
yielded some pottery vases, together with objects of copper and beads of
a peculiar precious stone called _callaïs_. All the finds made in the
megalithic remains of Spain and Portugal point to the period of
transition from the age of stone to that of metal.

The Balearic Islands contain remarkable megalithic monuments. Those
known as the _talayots_ are towers having a circular or rarely a square
base and sloping slightly inwards as they rise. The largest is 50 feet
in diameter. The stones, which are rather large and occasionally
trimmed, are laid flat, not on edge. A doorway just large enough to be
entered with comfort leads through the thickness of the wall into a
round chamber roofed by corbelling, with the assistance sometimes of one
or more pillars. From analogy with the _nuraghi_ of Sardinia, which they
resemble rather closely, it seems probable that the _talayots_ are
fortified dwellings, perhaps only used in time of danger (Fig. 15).

[Illustration: Fig. 15. Section and plan of the Talayot of Sa Aquila,
Majorca. (After Cartailhac.)]

[Illustration: Fig. 16. Nau d'Es Tudons, plan and section.
(After Cartailhac.)]

The _naus_ or _navetas_ are so named from their resemblance to ships.
The construction is similar to that of the _talayots_. The outer wall
has a considerable batter. The famous Nau d'Es Tudons is about 36 feet