The spatial tests can be found in the hibernate-spatial sub-module: https://github.com/hibernate/hibernate-orm/tree/main/hibernate-spatial/src/test/java/org/hibernate/spatial/testing

You don’t need to use the spatial dialects anymore, but you still need Hibernate Spatial to be on your classpath. You can create a test case by using e.g. https://github.com/hibernate/hibernate-test-case-templates/tree/main/orm/hibernate-orm-6 and adding a dependency on the hibernate-spatial module.