290 OUR FEDERAL LANDS 



ument creations of its rivals. Also, each declines to 

 approach the others with propositions to work out 

 joint standards and common control, and, as Con- 

 gress is altogether likely to take the system into its 

 own control if asked to interfere, thus subjecting it 

 to local and political influences which the present 

 system of creation reduces to a minimum, the situa- 

 tion may remain as it is unaltered for years unless 

 the National Conference on Outdoor Recreation suc- 

 ceeds in bringing about co-operation among the De- 

 partments concerned. 



A list of National Monuments in order of crea- 

 tion, their location, areas and differentiating char- 

 acteristics, appears in this chapter. Analyzed, they 

 fall into these groups : 



14 Prehistoric dwellings, or groups of dwell- 

 ings, of the pueblo type. 



5 Ruins of the early Spanish invasion. 



14 Places of later historic interest. 



22 Areas of special geologic significance. 

 3 Areas conserving wild life. 



Remains of prehistoric civilization dot our 

 Southwest freely. Ruins of very ancient cliff houses, 

 pueblos, irrigation systems and places of worship 

 are specially numerous in Colorado, New Mexico 

 and Arizona. The most fully developed and best 

 preserved of all are conserved in the Mesa Verde 

 National Park. Fourteen others chosen by archaeolo- 

 gists out of thousands, have been preserved in Na- 

 tional Monuments. They are: Montezuma Castle, 



