INSCRIPTIONS OF THE MIDDLE PERIOD. 211 
of its Acropolis, as exposed by the river, indicates a long period of growth. 
In the vertical section cut by the river a number of paved plaza-floors at 
different levels, as well as the walls of earlier buildings and drains, may be 
distinguished. To account for this architectural complex, even as it was 
during the Middle Period, it is necessary to postulate a considerable antiquity 
of origin, extending back into the Early Period. Probably from the 
earliest times the fertility of the land along the river, subject as it was to 
annual overflow, had been recognized, and it is quite likely that a settlement 
had been made here very early. But that it did not become the most impor- 
tant in the valley until after 9.11.15.0.0, the date of Stela 1, is probable from 
the facts already presented. Possibly the erection of Stele 10 and 12, which 
antedate the building of the Great Plaza by at least 25 years, in such a way 
that they define a line of sight across the Main Structure, may have had some- 
thing to do with increasing the importance of an earlier settlement already 
located here. 
The Main Structure may have been started in the Early Period, but 
if so, it did not assume the important position it later enjoyed until the 
Middle Period was well under way. Thus it seems likely that most, if not 
all, of the monuments found there, which antedate 9.11.15.0.0,! and some 
possibly even of later date,’ can not be regarded as in situ. The Great Plaza, 
we have seen, was not laid out until at least 10 years later (9.12.5.0.0), and 
possibly not for another 25 years (9.13.10.0.0). 
By 9.13.10.0.0, however (the date of Stela J), the Main Structure seems 
to have become the chief settlement in the valley, and Old Copan fell back 
into a position of secondary importance. By this time the Great Plaza was 
probably laid out in its final form, and its construction was well under way, 
if not indeed actually nearing completion. But even with the adoption of the 
Main Structure as the principal settlement or capital, the practice of erecting 
monuments in the outlying communities does not appear to have been discon- 
tinued altogether. Old Copan, as we shall see later (see p. 334), was occupied 
down to the close of the Great Period, and at least two other groups besides 
the Main Structure—No. 10, that near the modern cemetery, and No. 8, 
that just east of the Rio Sesesmil—had later monuments erected at them.° 
(See plate 3.) 
Of the monuments at the Main Structure dating from the last half of 
the Middle Period, with the exception of Stele I and J, that is to say, Altars 
K, H’, and I’, not one is in situ, strictly speaking, probably having been 
carried to their present positions from other earlier ones. 
The closing katun of the Middle Period, 9.14.0.0.0 to 9.15.0.0.0, does not 
seem to be represented by any monuments, either large or small. Perhaps 
there was a concentration of energy elsewhere, possibly all available labor 

1 Stel 16, 17, E, and P, Altars Y and A’ of the Early Period, and perhaps Stele 2 and 3 of the Middle Period. 
2 Altars K, H’,and I’. 
3 Stela 8 (9.17.12.6.2) was found practically in situ at what is now the modern cemetery (Group 10), and 
Stele 6 and 5 (9.12.10.0.0 and 9.13.15.0.0 or 9.14.0.0.0 respectively) were found, also probably zm situ, at the 
small group of mounds just east of the Rio Sesesmil (Group 8). 
