diff --git a/.github/workflows/tests.yml b/.github/workflows/tests.yml
index f9847839..b083b656 100644
--- a/.github/workflows/tests.yml
+++ b/.github/workflows/tests.yml
@@ -18,10 +18,12 @@ jobs:
           --health-interval 10s
           --health-timeout 5s
           --health-retries 5
+    env:
+      BUNDLE_GEMFILE: ${{matrix.gemfile}}
     strategy:
       matrix:
         ruby: [3.0, 2.7, 2.6, 2.5]
-        BUNDLE_GEMFILE:
+        gemfile:
           - gemfiles/ar61.gemfile
         pg: [9.6-3.0, 10-2.5, 11-3.0, 12-master, 13-master]
     steps:
diff --git a/History.md b/History.md
index ffa44c84..3aada46a 100644
--- a/History.md
+++ b/History.md
@@ -1,6 +1,12 @@
+### HEAD
+
+* Support Attributes #334
+* Access `configuration_hash` using symbols #335
+
 ### 7.0.1 / 2021-01-13
 
 * Fix db:gis:setup task #329
+
 ### 7.0.0 / 2020-12-22
 
 * Add ActiveRecord 6.1 Compatability (tagliala) #324
diff --git a/README.md b/README.md
index 8ff7a40e..700154e4 100644
--- a/README.md
+++ b/README.md
@@ -29,7 +29,29 @@ RGeo objects can be embedded in where clauses.
 
 ## Install
 
-The adapter requires PostgreSQL 9.0+.
+The adapter requires PostgreSQL 9.0+ and PostGIS 2.4+.
+
+### Installing PostGIS
+
+Here are common methods for installing PostGIS, but more detailed methods can be found on the [installation guide](https://postgis.net/install/).
+
+#### MacOS
+
+```sh
+brew install postgis
+```
+
+#### Ubuntu/Debian
+
+```sh
+# The second package can be replaced depending on your postgresql version
+# ex. postgresql-11-postgis-2 is valid as well
+sudo apt-get install postgis postgresql-12-postgis-3
+```
+
+#### Windows
+
+PostGIS is likely available as an optional package via your Postgresql installer. If not, refer to the installation guide.
 
 Gemfile:
 
@@ -305,6 +327,18 @@ change_table :my_table do |t|
 end
 ```
 
+### Attributes
+
+Models may also define attributes using the above data types and options.
+
+```ruby
+class SpatialModel < ActiveRecord::Base
+  attribute :centroid, :st_point, srid: 4326, geographic: true
+end
+```
+
+`centroid` will not have an associated column in the `spatial_models` table, but any geometry object assigned to the `centroid` attribute will be cast to a geographic point.
+
 ### Point and Polygon Types with ActiveRecord 4.2+
 
 Prior to version 3, the `point` and `polygon` types were supported. In ActiveRecord 4.2, the Postgresql
@@ -489,6 +523,32 @@ containing_buiildings = Building.where(buildings[:geom].st_contains(point))
 
 See [rgeo-activerecord](https://github.com/rgeo/rgeo-activerecord) for more information about advanced spatial queries.
 
+### Joining Spatial Columns
+
+If a spatial column is joined with another model, `srid` and `geographic` will not be automatically inferred and they will default to 0 and `false`, by default. In order to properly infer these options after a join, an `attribute` must be created on the target table.
+
+```ruby
+class SpatialModel < ActiveRecord::Base
+ belongs_to :foo
+
+ # has column geo_point (:st_point, srid: 4326, geographic: true)
+end
+
+class Foo < ActiveRecord::Base
+ has_one :spatial_model
+
+ # re-define geo_point here so join works
+ attribute :geo_point, :st_point, srid: 4326, geographic: true
+end
+
+# perform a query where geo_point is joined to foo
+foo = Foo.joins(:spatial_models).select("foos.id, spatial_models.geo_point").first
+p foo.geo_point.class
+# => RGeo::Geographic::SphericalPointImpl
+p foo.geo_point.srid
+# => 4326
+```
+
 ## Background: PostGIS
 
 A spatial database is one that includes a set of data types, functions,
diff --git a/lib/active_record/connection_adapters/postgis/oid/spatial.rb b/lib/active_record/connection_adapters/postgis/oid/spatial.rb
index 50eb2aa2..b97cb155 100644
--- a/lib/active_record/connection_adapters/postgis/oid/spatial.rb
+++ b/lib/active_record/connection_adapters/postgis/oid/spatial.rb
@@ -4,16 +4,17 @@ module ActiveRecord
   module ConnectionAdapters
     module PostGIS
       module OID
+        # OID used to represent geometry/geography database types and attributes.
+        #
+        # Accepts `geo_type`, `srid`, `has_z`, `has_m`, and `geographic` as parameters.
+        # Responsible for parsing sql_types returned from the database and WKT features.
         class Spatial < Type::Value
-          # sql_type is a string that comes from the database definition
-          # examples:
-          #   "geometry(Point,4326)"
-          #   "geography(Point,4326)"
-          #   "geometry(Polygon,4326) NOT NULL"
-          #   "geometry(Geography,4326)"
-          def initialize(oid, sql_type)
-            @sql_type = sql_type
-            @geo_type, @srid, @has_z, @has_m = self.class.parse_sql_type(sql_type)
+          def initialize(geo_type: 'geometry', srid: 0, has_z: false, has_m: false, geographic: false)
+            @geo_type = geo_type
+            @srid = srid
+            @has_z = has_z
+            @has_m = has_m
+            @geographic = geographic
           end
 
           # sql_type: geometry, geometry(Point), geometry(Point,4326), ...
@@ -43,7 +44,9 @@ def self.parse_sql_type(sql_type)
               # otherType(a,b)
               geo_type = sql_type
             end
-            [geo_type, srid, has_z, has_m]
+            geographic = sql_type.match?(/geography/)
+
+            [geo_type, srid, has_z, has_m, geographic]
           end
 
           def spatial_factory
@@ -53,16 +56,12 @@ def spatial_factory
               )
           end
 
-          def geographic?
-            @sql_type =~ /geography/
-          end
-
           def spatial?
             true
           end
 
           def type
-            geographic? ? :geography : :geometry
+            @geographic ? :geography : :geometry
           end
 
           # support setting an RGeo object or a WKT string
diff --git a/lib/active_record/connection_adapters/postgis/schema_statements.rb b/lib/active_record/connection_adapters/postgis/schema_statements.rb
index 1a1be6a4..cf88ea1b 100644
--- a/lib/active_record/connection_adapters/postgis/schema_statements.rb
+++ b/lib/active_record/connection_adapters/postgis/schema_statements.rb
@@ -96,8 +96,15 @@ def initialize_type_map(map = type_map)
             st_point
             st_polygon
           ).each do |geo_type|
-            map.register_type(geo_type) do |oid, _, sql_type|
-              OID::Spatial.new(oid, sql_type)
+            map.register_type(geo_type) do |_, _, sql_type|
+              # sql_type is a string that comes from the database definition
+              # examples:
+              #   "geometry(Point,4326)"
+              #   "geography(Point,4326)"
+              #   "geometry(Polygon,4326) NOT NULL"
+              #   "geometry(Geography,4326)"
+              geo_type, srid, has_z, has_m, geographic = OID::Spatial.parse_sql_type(sql_type)
+              OID::Spatial.new(geo_type: geo_type, srid: srid, has_z: has_z, has_m: has_m, geographic: geographic)
             end
           end
 
diff --git a/lib/active_record/connection_adapters/postgis/spatial_column.rb b/lib/active_record/connection_adapters/postgis/spatial_column.rb
index 528f72f9..75c1e7d4 100644
--- a/lib/active_record/connection_adapters/postgis/spatial_column.rb
+++ b/lib/active_record/connection_adapters/postgis/spatial_column.rb
@@ -67,7 +67,7 @@ def set_geometric_type_from_name(name)
         end
 
         def build_from_sql_type(sql_type)
-          geo_type, @srid, @has_z, @has_m = OID::Spatial.parse_sql_type(sql_type)
+          geo_type, @srid, @has_z, @has_m, @geographic = OID::Spatial.parse_sql_type(sql_type)
           set_geometric_type_from_name(geo_type)
         end
 
diff --git a/lib/active_record/connection_adapters/postgis/type.rb b/lib/active_record/connection_adapters/postgis/type.rb
new file mode 100644
index 00000000..babd22c5
--- /dev/null
+++ b/lib/active_record/connection_adapters/postgis/type.rb
@@ -0,0 +1,22 @@
+# frozen_string_literal: true
+
+module ActiveRecord
+  module ConnectionAdapters
+    module PostGIS
+      module Type
+        # Look for :postgis types first, then check for :postgresql
+        # types to simulate a kind of Type inheritance.
+        def lookup(*args, adapter: current_adapter_name, **kwargs)
+          super(*args, adapter: adapter, **kwargs)
+        rescue ArgumentError => e
+          raise e unless current_adapter_name == :postgis
+
+          super(*args, adapter: :postgresql, **kwargs)
+        end
+      end
+    end
+  end
+
+  # Type uses `class << self` syntax so we have to prepend to the singleton_class
+  Type.singleton_class.prepend(ActiveRecord::ConnectionAdapters::PostGIS::Type)
+end
diff --git a/lib/active_record/connection_adapters/postgis_adapter.rb b/lib/active_record/connection_adapters/postgis_adapter.rb
index c60ee076..65a81205 100644
--- a/lib/active_record/connection_adapters/postgis_adapter.rb
+++ b/lib/active_record/connection_adapters/postgis_adapter.rb
@@ -18,6 +18,7 @@
 require "active_record/connection_adapters/postgis/arel_tosql"
 require "active_record/connection_adapters/postgis/setup"
 require "active_record/connection_adapters/postgis/oid/spatial"
+require "active_record/connection_adapters/postgis/type" # has to be after oid/*
 require "active_record/connection_adapters/postgis/create_connection"
 require "active_record/connection_adapters/postgis/postgis_database_tasks"
 
@@ -87,6 +88,21 @@ def quote(value)
           super
         end
       end
+
+      # PostGIS specific types
+      [
+        :geography,
+        :geometry,
+        :geometry_collection,
+        :line_string,
+        :multi_line_string,
+        :multi_point,
+        :multi_polygon,
+        :st_point,
+        :st_polygon,
+      ].each do |geo_type|
+        ActiveRecord::Type.register(geo_type, PostGIS::OID::Spatial, adapter: :postgis)
+      end
     end
   end
 end
diff --git a/test/attributes_test.rb b/test/attributes_test.rb
new file mode 100644
index 00000000..e53ad251
--- /dev/null
+++ b/test/attributes_test.rb
@@ -0,0 +1,117 @@
+# frozen_string_literal: true
+
+require "test_helper"
+
+class Foo < ActiveRecord::Base
+  establish_test_connection
+  has_one :spatial_foo
+  attribute :bar, :string, array: true
+  attribute :baz, :string, range: true
+end
+
+class SpatialFoo < ActiveRecord::Base
+  establish_test_connection
+  attribute :point, :st_point, srid: 3857
+  attribute :pointz, :st_point, has_z: true, srid: 3509
+  attribute :pointm, :st_point, has_m: true, srid: 3509
+  attribute :polygon, :st_polygon, srid: 3857
+  attribute :path, :line_string, srid: 3857
+  attribute :geo_path, :line_string, geographic: true, srid: 4326
+end
+
+class InvalidAttribute < ActiveRecord::Base
+  establish_test_connection
+end
+
+class AttributesTest < ActiveSupport::TestCase
+  def setup
+    reset_spatial_store
+    create_foo
+    create_spatial_foo
+    create_invalid_attributes
+  end
+
+  def test_postgresql_attributes_registered
+    assert Foo.attribute_names.include?("bar")
+    assert Foo.attribute_names.include?("baz")
+
+    data = Foo.new
+    data.bar = %w[a b c]
+    data.baz = "1".."3"
+
+    assert_equal data.bar, %w[a b c]
+    assert_equal data.baz, "1".."3"
+  end
+
+  def test_invalid_attribute
+    assert_raises(ArgumentError) do
+      InvalidAttribute.attribute(:attr, :invalid_attr)
+      InvalidAttribute.new
+    end
+  end
+
+  def test_spatial_attributes
+    data = SpatialFoo.new
+    data.point = "POINT(0 0)"
+    data.pointz = "POINT(0 0 1)"
+    data.pointm = "POINT(0 0 2)"
+    data.polygon = "POLYGON((0 0, 0 1, 1 1, 1 0, 0 0))"
+    data.path = "LINESTRING(0 0, 0 1, 1 1, 1 0, 0 0)"
+    data.geo_path = "LINESTRING(-75.165222 39.952583,-73.561668 45.508888)"
+
+    assert_equal 3857, data.point.srid
+    assert_equal 0, data.point.x
+    assert_equal 0, data.point.y
+
+    assert_equal 3509, data.pointz.srid
+    assert_equal 1, data.pointz.z
+
+    assert_equal 3509, data.pointm.srid
+    assert_equal 2, data.pointm.m
+
+    assert_equal 3857, data.polygon.srid
+    assert_equal 3857, data.path.srid
+    assert_equal data.path, data.polygon.exterior_ring
+
+    assert_equal 4326, data.geo_path.srid
+    assert_equal RGeo::Geographic::Factory, data.geo_path.factory.class
+  end
+
+  def test_joined_spatial_attribute
+    # TODO: The attributes that will be joined have to be defined on the
+    # model we make the query with. Ideally, it would "just work" but
+    # at least this workaround makes joining functional.
+    Foo.attribute :geo_point, :st_point, srid: 4326, geographic: true
+    Foo.attribute :cart_point, :st_point, srid: 3509
+
+    foo = Foo.create
+    SpatialFoo.create(foo_id: foo.id, geo_point: "POINT(10 10)", cart_point: "POINT(2 2)")
+
+    # query foo and join child spatial foo on it
+    foo = Foo.joins(:spatial_foo).select("foos.id, spatial_foos.geo_point, spatial_foos.cart_point").first
+    assert_equal 4326, foo.geo_point.srid
+    assert_equal 3509, foo.cart_point.srid
+    assert_equal foo.geo_point, SpatialFoo.first.geo_point
+    assert_equal foo.cart_point, SpatialFoo.first.cart_point
+  end
+
+  private
+
+  def create_foo
+    Foo.connection.create_table :foos, force: true do |t|
+    end
+  end
+
+  def create_spatial_foo
+    SpatialFoo.connection.create_table :spatial_foos, force: true do |t|
+      t.references :foo
+      t.st_point :geo_point, geographic: true, srid: 4326
+      t.st_point :cart_point, srid: 3509
+    end
+  end
+
+  def create_invalid_attributes
+    InvalidAttribute.connection.create_table :invalid_attributes, force: true do |t|
+    end
+  end
+end
diff --git a/test/basic_test.rb b/test/basic_test.rb
index 1bb6e932..2e36ab8a 100644
--- a/test/basic_test.rb
+++ b/test/basic_test.rb
@@ -3,6 +3,10 @@
 require "test_helper"
 
 class BasicTest < ActiveSupport::TestCase
+  def setup
+    reset_spatial_store
+  end
+
   def test_version
     refute_nil ActiveRecord::ConnectionAdapters::PostGIS::VERSION
   end
@@ -112,7 +116,6 @@ def test_custom_factory
     object.save!
     object.reload
     assert_equal area.to_s, object.area.to_s
-    spatial_factory_store.clear
   end
 
   def test_spatial_factory_attrs_parsing
@@ -135,8 +138,6 @@ def test_spatial_factory_attrs_parsing
     object.save!
     object.reload
     assert_equal(factory, object.areas.factory)
-
-    spatial_factory_store.clear
   end
 
   def test_readme_example
@@ -165,8 +166,6 @@ def test_readme_example
     object.save!
     object.reload
     refute_equal geo_factory, object.shape.factory
-
-    spatial_factory_store.clear
   end
 
   def test_point_to_json
diff --git a/test/test_helper.rb b/test/test_helper.rb
index c1dace16..93820347 100644
--- a/test/test_helper.rb
+++ b/test/test_helper.rb
@@ -21,6 +21,8 @@ def self.establish_test_connection
   end
 end
 
+ActiveRecord::Base.establish_test_connection
+
 class SpatialModel < ActiveRecord::Base
   establish_test_connection
 end
@@ -48,5 +50,10 @@ def geographic_factory
     def spatial_factory_store
       RGeo::ActiveRecord::SpatialFactoryStore.instance
     end
+
+    def reset_spatial_store
+      spatial_factory_store.clear
+      spatial_factory_store.default = nil
+    end
   end
 end
diff --git a/test/type_test.rb b/test/type_test.rb
index a69a4a0b..a6c1b873 100644
--- a/test/type_test.rb
+++ b/test/type_test.rb
@@ -4,33 +4,33 @@
 
 class TypeTest < ActiveSupport::TestCase
   def test_parse_simple_type
-    assert_equal ["geometry", 0, false, false], spatial.parse_sql_type("geometry")
-    assert_equal ["geography", 0, false, false], spatial.parse_sql_type("geography")
+    assert_equal ["geometry", 0, false, false, false], spatial.parse_sql_type("geometry")
+    assert_equal ["geography", 0, false, false, true], spatial.parse_sql_type("geography")
   end
 
   def test_parse_geo_type
-    assert_equal ["Point", 0, false, false], spatial.parse_sql_type("geography(Point)")
-    assert_equal ["Point", 0, false, true], spatial.parse_sql_type("geography(PointM)")
-    assert_equal ["Point", 0, true, false], spatial.parse_sql_type("geography(PointZ)")
-    assert_equal ["Point", 0, true, true], spatial.parse_sql_type("geography(PointZM)")
-    assert_equal ["Polygon", 0, false, false], spatial.parse_sql_type("geography(Polygon)")
-    assert_equal ["Polygon", 0, true, false], spatial.parse_sql_type("geography(PolygonZ)")
-    assert_equal ["Polygon", 0, false, true], spatial.parse_sql_type("geography(PolygonM)")
-    assert_equal ["Polygon", 0, true, true], spatial.parse_sql_type("geography(PolygonZM)")
+    assert_equal ["Point", 0, false, false, true], spatial.parse_sql_type("geography(Point)")
+    assert_equal ["Point", 0, false, true, true], spatial.parse_sql_type("geography(PointM)")
+    assert_equal ["Point", 0, true, false, true], spatial.parse_sql_type("geography(PointZ)")
+    assert_equal ["Point", 0, true, true, true], spatial.parse_sql_type("geography(PointZM)")
+    assert_equal ["Polygon", 0, false, false, true], spatial.parse_sql_type("geography(Polygon)")
+    assert_equal ["Polygon", 0, true, false, true], spatial.parse_sql_type("geography(PolygonZ)")
+    assert_equal ["Polygon", 0, false, true, true], spatial.parse_sql_type("geography(PolygonM)")
+    assert_equal ["Polygon", 0, true, true, true], spatial.parse_sql_type("geography(PolygonZM)")
   end
 
   def test_parse_type_with_srid
-    assert_equal ["Point", 4326, false, false], spatial.parse_sql_type("geography(Point,4326)")
-    assert_equal ["Polygon", 4327, true, false], spatial.parse_sql_type("geography(PolygonZ,4327)")
-    assert_equal ["Point", 4328, false, true], spatial.parse_sql_type("geography(PointM,4328)")
-    assert_equal ["Point", 4329, true, true], spatial.parse_sql_type("geography(PointZM,4329)")
-    assert_equal ["MultiPolygon", 4326, false, false], spatial.parse_sql_type("geometry(MultiPolygon,4326)")
+    assert_equal ["Point", 4326, false, false, true], spatial.parse_sql_type("geography(Point,4326)")
+    assert_equal ["Polygon", 4327, true, false, true], spatial.parse_sql_type("geography(PolygonZ,4327)")
+    assert_equal ["Point", 4328, false, true, true], spatial.parse_sql_type("geography(PointM,4328)")
+    assert_equal ["Point", 4329, true, true, true], spatial.parse_sql_type("geography(PointZM,4329)")
+    assert_equal ["MultiPolygon", 4326, false, false, false], spatial.parse_sql_type("geometry(MultiPolygon,4326)")
   end
 
   def test_parse_non_geo_types
-    assert_equal ["x", 0, false, false], spatial.parse_sql_type("x")
-    assert_equal ["foo", 0, false, false], spatial.parse_sql_type("foo")
-    assert_equal ["foo(A,1234)", 0, false, false], spatial.parse_sql_type("foo(A,1234)")
+    assert_equal ["x", 0, false, false, false], spatial.parse_sql_type("x")
+    assert_equal ["foo", 0, false, false, false], spatial.parse_sql_type("foo")
+    assert_equal ["foo(A,1234)", 0, false, false, false], spatial.parse_sql_type("foo(A,1234)")
   end
 
   private