diff --git a/ouroboros-consensus-cardano/src/Ouroboros/Consensus/Cardano.hs b/ouroboros-consensus-cardano/src/Ouroboros/Consensus/Cardano.hs
index c2733d3dbf7..5ecd3e0884c 100644
--- a/ouroboros-consensus-cardano/src/Ouroboros/Consensus/Cardano.hs
+++ b/ouroboros-consensus-cardano/src/Ouroboros/Consensus/Cardano.hs
@@ -70,7 +70,6 @@ import           Ouroboros.Consensus.Cardano.ShelleyHFC
 
 type ProtocolByron   = HardForkProtocol '[ ByronBlock ]
 type ProtocolShelley = HardForkProtocol '[ ShelleyBlock StandardShelley ]
-type ProtocolMary    = HardForkProtocol '[ ShelleyBlock StandardMary ]
 type ProtocolCardano = HardForkProtocol '[ ByronBlock
                                          , ShelleyBlock StandardShelley
                                          , ShelleyBlock StandardAllegra
@@ -94,12 +93,6 @@ data Protocol (m :: Type -> Type) blk p where
     -> ProtocolParamsShelley
     -> Protocol m (ShelleyBlockHFC StandardShelley) ProtocolShelley
 
-  -- | Run TPraos against the Mary ledger
-  ProtocolMary
-    :: ProtocolParamsShelleyBased StandardMary
-    -> ProtocolParamsMary
-    -> Protocol m (ShelleyBlockHFC StandardMary) ProtocolMary
-
   -- | Run the protocols of /the/ Cardano block
   --
   -- WARNING: only a single set of Shelley credentials is allowed when used for
@@ -124,7 +117,6 @@ data Protocol (m :: Type -> Type) blk p where
 verifyProtocol :: Protocol m blk p -> (p :~: BlockProtocol blk)
 verifyProtocol ProtocolByron{}   = Refl
 verifyProtocol ProtocolShelley{} = Refl
-verifyProtocol ProtocolMary{}    = Refl
 verifyProtocol ProtocolCardano{} = Refl
 
 {-------------------------------------------------------------------------------
@@ -140,9 +132,6 @@ protocolInfo (ProtocolByron params) =
 protocolInfo (ProtocolShelley paramsShelleyBased paramsShelley) =
     inject $ protocolInfoShelley paramsShelleyBased paramsShelley
 
-protocolInfo (ProtocolMary paramsShelleyBased paramsMary) =
-    inject $ protocolInfoMary paramsShelleyBased paramsMary
-
 protocolInfo (ProtocolCardano
                paramsByron
                paramsShelleyBased
@@ -169,7 +158,6 @@ protocolInfo (ProtocolCardano
 runProtocol :: Protocol m blk p -> Dict (RunNode blk)
 runProtocol ProtocolByron{}   = Dict
 runProtocol ProtocolShelley{} = Dict
-runProtocol ProtocolMary{}    = Dict
 runProtocol ProtocolCardano{} = Dict
 
 {-------------------------------------------------------------------------------
diff --git a/ouroboros-consensus-shelley/src/Ouroboros/Consensus/Shelley/Node.hs b/ouroboros-consensus-shelley/src/Ouroboros/Consensus/Shelley/Node.hs
index 81610488b94..a3a91dca093 100644
--- a/ouroboros-consensus-shelley/src/Ouroboros/Consensus/Shelley/Node.hs
+++ b/ouroboros-consensus-shelley/src/Ouroboros/Consensus/Shelley/Node.hs
@@ -20,7 +20,6 @@
 module Ouroboros.Consensus.Shelley.Node (
     protocolInfoShelleyBased
   , protocolInfoShelley
-  , protocolInfoMary
   , ProtocolParamsShelleyBased (..)
   , ProtocolParamsShelley (..)
   , ProtocolParamsAllegra (..)
@@ -253,17 +252,6 @@ protocolInfoShelley protocolParamsShelleyBased
                       } =
     protocolInfoShelleyBased protocolParamsShelleyBased protVer
 
-protocolInfoMary ::
-     forall m c. (IOLike m, ShelleyBasedEra (MaryEra c))
-  => ProtocolParamsShelleyBased (MaryEra c)
-  -> ProtocolParamsMary
-  -> ProtocolInfo m (ShelleyBlock (MaryEra c))
-protocolInfoMary protocolParamsShelleyBased
-                 ProtocolParamsMary {
-                     maryProtVer = protVer
-                   } =
-    protocolInfoShelleyBased protocolParamsShelleyBased protVer
-
 protocolInfoShelleyBased ::
      forall m era. (IOLike m, ShelleyBasedEra era)
   => ProtocolParamsShelleyBased era