diff --git a/services/horizon/cmd/db.go b/services/horizon/cmd/db.go
index 351a265100..819a6b3cbe 100644
--- a/services/horizon/cmd/db.go
+++ b/services/horizon/cmd/db.go
@@ -374,17 +374,14 @@ var dbFillGapsCmd = &cobra.Command{
 }
 
 func runDBReingestRange(ledgerRanges []history.LedgerRange, reingestForce bool, parallelWorkers uint, config horizon.Config) error {
+	var err error
+
 	if reingestForce && parallelWorkers > 1 {
 		return errors.New("--force is incompatible with --parallel-workers > 1")
 	}
-	horizonSession, err := db.Open("postgres", config.DatabaseURL)
-	if err != nil {
-		return fmt.Errorf("cannot open Horizon DB: %v", err)
-	}
 
 	ingestConfig := ingest.Config{
 		NetworkPassphrase:           config.NetworkPassphrase,
-		HistorySession:              horizonSession,
 		HistoryArchiveURL:           config.HistoryArchiveURLs[0],
 		CheckpointFrequency:         config.CheckpointFrequency,
 		MaxReingestRetries:          int(retries),
@@ -400,15 +397,18 @@ func runDBReingestRange(ledgerRanges []history.LedgerRange, reingestForce bool,
 		RoundingSlippageFilter:      config.RoundingSlippageFilter,
 	}
 
-	if !ingestConfig.EnableCaptiveCore {
+	if ingestConfig.HistorySession, err = db.Open("postgres", config.DatabaseURL); err != nil {
+		return fmt.Errorf("cannot open Horizon DB: %v", err)
+	}
+
+	if !config.EnableCaptiveCoreIngestion {
 		if config.StellarCoreDatabaseURL == "" {
 			return fmt.Errorf("flag --%s cannot be empty", horizon.StellarCoreDBURLFlagName)
 		}
-		coreSession, dbErr := db.Open("postgres", config.StellarCoreDatabaseURL)
-		if dbErr != nil {
-			return fmt.Errorf("cannot open Core DB: %v", dbErr)
+		if ingestConfig.CoreSession, err = db.Open("postgres", config.StellarCoreDatabaseURL); err != nil {
+			ingestConfig.HistorySession.Close()
+			return fmt.Errorf("cannot open Core DB: %v", err)
 		}
-		ingestConfig.CoreSession = coreSession
 	}
 
 	if parallelWorkers > 1 {
@@ -427,6 +427,7 @@ func runDBReingestRange(ledgerRanges []history.LedgerRange, reingestForce bool,
 	if systemErr != nil {
 		return systemErr
 	}
+	defer system.Shutdown()
 
 	err = system.ReingestRange(ledgerRanges, reingestForce)
 	if err != nil {
@@ -479,6 +480,7 @@ func runDBDetectGaps(config horizon.Config) ([]history.LedgerRange, error) {
 	if err != nil {
 		return nil, err
 	}
+	defer horizonSession.Close()
 	q := &history.Q{horizonSession}
 	return q.GetLedgerGaps(context.Background())
 }
@@ -488,6 +490,7 @@ func runDBDetectGapsInRange(config horizon.Config, start, end uint32) ([]history
 	if err != nil {
 		return nil, err
 	}
+	defer horizonSession.Close()
 	q := &history.Q{horizonSession}
 	return q.GetLedgerGapsInRange(context.Background(), start, end)
 }
diff --git a/services/horizon/internal/db2/history/main.go b/services/horizon/internal/db2/history/main.go
index 2fdd76b3f4..0e05b8dc26 100644
--- a/services/horizon/internal/db2/history/main.go
+++ b/services/horizon/internal/db2/history/main.go
@@ -268,6 +268,7 @@ type IngestionQ interface {
 	BeginTx(*sql.TxOptions) error
 	Commit() error
 	CloneIngestionQ() IngestionQ
+	Close() error
 	Rollback() error
 	GetTx() *sqlx.Tx
 	GetIngestVersion(context.Context) (int, error)
diff --git a/services/horizon/internal/ingest/main.go b/services/horizon/internal/ingest/main.go
index 26f66bddb0..02956f74e6 100644
--- a/services/horizon/internal/ingest/main.go
+++ b/services/horizon/internal/ingest/main.go
@@ -697,6 +697,7 @@ func (s *system) Shutdown() {
 	s.cancel()
 	// wait for ingestion state machine to terminate
 	s.wg.Wait()
+	s.historyQ.Close()
 	if err := s.ledgerBackend.Close(); err != nil {
 		log.WithError(err).Info("could not close ledger backend")
 	}
diff --git a/services/horizon/internal/ingest/main_test.go b/services/horizon/internal/ingest/main_test.go
index bd56ef5bd7..ae54acc0f1 100644
--- a/services/horizon/internal/ingest/main_test.go
+++ b/services/horizon/internal/ingest/main_test.go
@@ -265,6 +265,11 @@ func (m *mockDBQ) Commit() error {
 	return args.Error(0)
 }
 
+func (m *mockDBQ) Close() error {
+	args := m.Called()
+	return args.Error(0)
+}
+
 func (m *mockDBQ) Rollback() error {
 	args := m.Called()
 	return args.Error(0)
diff --git a/services/horizon/internal/ingest/parallel.go b/services/horizon/internal/ingest/parallel.go
index 547098ed0d..b3c163689d 100644
--- a/services/horizon/internal/ingest/parallel.go
+++ b/services/horizon/internal/ingest/parallel.go
@@ -47,6 +47,16 @@ func newParallelSystems(config Config, workerCount uint, systemFactory func(Conf
 	}, nil
 }
 
+func (ps *ParallelSystems) Shutdown() {
+	log.Info("Shutting down parallel ingestion system...")
+	if ps.config.HistorySession != nil {
+		ps.config.HistorySession.Close()
+	}
+	if ps.config.CoreSession != nil {
+		ps.config.CoreSession.Close()
+	}
+}
+
 func (ps *ParallelSystems) runReingestWorker(s System, stop <-chan struct{}, reingestJobQueue <-chan history.LedgerRange) rangeError {
 
 	for {
@@ -128,6 +138,9 @@ func (ps *ParallelSystems) ReingestRange(ledgerRanges []history.LedgerRange, bat
 		// the user needs to start again to prevent the gaps.
 		lowestRangeErr *rangeError
 	)
+
+	defer ps.Shutdown()
+
 	if err := validateRanges(ledgerRanges); err != nil {
 		return err
 	}
diff --git a/services/horizon/internal/integration/db_test.go b/services/horizon/internal/integration/db_test.go
index 376af8e607..9da5ed59ad 100644
--- a/services/horizon/internal/integration/db_test.go
+++ b/services/horizon/internal/integration/db_test.go
@@ -444,21 +444,7 @@ func TestReingestDB(t *testing.T) {
 	itest, reachedLedger := initializeDBIntegrationTest(t)
 	tt := assert.New(t)
 
-	// Create a fresh Horizon database
-	newDB := dbtest.Postgres(t)
-	// TODO: Unfortunately Horizon's ingestion System leaves open sessions behind,leading to
-	//       a "database  is being accessed by other users" error when trying to drop it
-	// defer newDB.Close()
-	freshHorizonPostgresURL := newDB.DSN
 	horizonConfig := itest.GetHorizonConfig()
-	horizonConfig.DatabaseURL = freshHorizonPostgresURL
-	// Initialize the DB schema
-	dbConn, err := db.Open("postgres", freshHorizonPostgresURL)
-	tt.NoError(err)
-	defer dbConn.Close()
-	_, err = schema.Migrate(dbConn.DB.DB, schema.MigrateUp, 0)
-	tt.NoError(err)
-
 	t.Run("validate parallel range", func(t *testing.T) {
 		horizoncmd.RootCmd.SetArgs(command(horizonConfig,
 			"db",
@@ -559,7 +545,13 @@ func TestFillGaps(t *testing.T) {
 	horizonConfig.DatabaseURL = freshHorizonPostgresURL
 	// Initialize the DB schema
 	dbConn, err := db.Open("postgres", freshHorizonPostgresURL)
-	defer dbConn.Close()
+	tt.NoError(err)
+	historyQ := history.Q{dbConn}
+	defer func() {
+		historyQ.Close()
+		newDB.Close()
+	}()
+
 	_, err = schema.Migrate(dbConn.DB.DB, schema.MigrateUp, 0)
 	tt.NoError(err)
 
@@ -603,7 +595,6 @@ func TestFillGaps(t *testing.T) {
 	// subprocesses to conflict.
 	itest.StopHorizon()
 
-	historyQ := history.Q{dbConn}
 	var oldestLedger, latestLedger int64
 	tt.NoError(historyQ.ElderLedger(context.Background(), &oldestLedger))
 	tt.NoError(historyQ.LatestLedger(context.Background(), &latestLedger))
diff --git a/services/horizon/internal/test/integration/integration.go b/services/horizon/internal/test/integration/integration.go
index 0c675ac4a1..92e8740d59 100644
--- a/services/horizon/internal/test/integration/integration.go
+++ b/services/horizon/internal/test/integration/integration.go
@@ -278,10 +278,8 @@ func (i *Test) StartHorizon() error {
 	if horizonPostgresURL == "" {
 		postgres := dbtest.Postgres(i.t)
 		i.shutdownCalls = append(i.shutdownCalls, func() {
-			// FIXME: Unfortunately, Horizon leaves open sessions behind,
-			//        leading to a "database is being accessed by other users"
-			//        error when trying to drop it.
-			// postgres.Close()
+			i.StopHorizon()
+			postgres.Close()
 		})
 		horizonPostgresURL = postgres.DSN
 	}
@@ -490,7 +488,11 @@ func (i *Test) Horizon() *horizon.App {
 
 // StopHorizon shuts down the running Horizon process
 func (i *Test) StopHorizon() {
-	i.app.CloseDB()
+	if i.app == nil {
+		// horizon has already been stopped
+		return
+	}
+
 	i.app.Close()
 
 	// Wait for Horizon to shut down completely.
diff --git a/support/db/dbtest/db.go b/support/db/dbtest/db.go
index bda67c49e8..6ab32b6926 100644
--- a/support/db/dbtest/db.go
+++ b/support/db/dbtest/db.go
@@ -132,6 +132,9 @@ func Postgres(t testing.TB) *DB {
 	result.DSN = fmt.Sprintf("postgres://%s@localhost/%s?sslmode=disable&timezone=UTC", pgUser, result.dbName)
 
 	result.closer = func() {
+		// pg_terminate_backend is a best effort, it does not gaurantee that it can close any lingering connections
+		// it sends a quit signal to each remaining connection in the db
+		execStatement(t, pgUser, "SELECT pg_terminate_backend(pid) FROM pg_stat_activity WHERE datname = '"+pq.QuoteIdentifier(result.dbName)+"';")
 		execStatement(t, pgUser, "DROP DATABASE "+pq.QuoteIdentifier(result.dbName))
 	}