After installing Tomcat with apt-get on Ubuntu xx.xx, Tomcat creates and uses these directories:
$cd /etc/tomcat6/
├── Catalina
│ └── localhost
│ ├── ROOT.xml
│ └── solr.xml -> ../../../solr/solr-tomcat.xml
├── catalina.properties
├── context.xml
├── logging.properties
├── ...
