Maven: Overview for the values of Maven properties

the maven-help-plugin does what you want, just call it with -Dexpression=project.properties this will print the properties tag of the effective pom.

tl;dr

mvn help:evaluate -Dexpression=project.properties

Bonus Points when you just want the properties output and not the maven output

mvn help:evaluate -Dexpression=project.properties -q -DforceStdout

or with the explicit version because -DforceStdout works since version 3.1.0

mvn org.apache.maven.plugins:maven-help-plugin:3.2.0:evaluate -Dexpression=project.properties -q -DforceStdout

As a workaround, add this to the <plugins> ... </plugins> section inside your project's pom.xml:

<plugin>
  <groupId>org.apache.maven.plugins</groupId>
  <artifactId>maven-antrun-plugin</artifactId>
  <version>1.7</version>
  <executions>
    <execution>
      <phase>validate</phase>
      <goals>
        <goal>run</goal>
      </goals>
      <configuration>
        <tasks>
          <echoproperties />
        </tasks>
      </configuration>
    </execution>
  </executions>
</plugin>

Now execute mvn validate.
On the console, prefixed with [echoproperties], there will be the full list of system properties, including those set by Maven such as project.build.outputDirectory, basedir, and settings.localRepository.