# List of Sites of Special Scientific Interest in Lincolnshire

This is a list of Sites of Special Scientific Interest (SSSIs) in Lincolnshire. This list includes sites within the ceremonial county of Lincolnshire, covering the two unitary authorities North Lincolnshire and North East Lincolnshire as well as the rest of the county administered by Lincolnshire County Council.
This list features 98 SSSIs notable for their biology, 23 notable for their geology and three notable for both. Six of the SSSIs include national nature reserves, four are Ramsar Wetland sites, and five are EU Special Protection Areas.
For other counties, see List of SSSIs by Area of Search.

## Sites

| Site name | Reason for designation | Reason for designation | Area | Area | Location & map ref | Year in which notified | Other designations | Map/Refs |
| Site name | Biological interest | Geological interest | Hectares | Acres | Location & map ref | Year in which notified | Other designations | Map/Refs |
| Allington Meadows | Y | | 3.8 | 9.3 | 52°56′53″N 0°42′25″W﻿ / ﻿52.948°N 0.707°W﻿ / 52.948; -0.707﻿ (Allington Meadows) SK870397 | 1987 | | Map |
| Ancaster Valley | Y | | 10.3 | 25.4 | 52°58′30″N 0°31′59″W﻿ / ﻿52.975°N 0.533°W﻿ / 52.975; -0.533﻿ (Ancaster Valley) SK986430 | 1951 | WT, NCR | Map |
| Bardney Limewoods | Y | | 539.8 | 1,333.9 | 53°14′49″N 0°17′06″W﻿ / ﻿53.247°N 0.285°W﻿ / 53.247; -0.285﻿ (Bardney Limewoods, Lincolnshire) TF145736 | 1959 | NNR, NCR, | Map |
| Baston And Thurlby Fens | Y | | 54.6 | 134.9 | 52°44′10″N 0°20′06″W﻿ / ﻿52.736°N 0.335°W﻿ / 52.736; -0.335﻿ (Baston And Thurlby Fens) TF125167 | 1968 | WT, NCR, SAC | Map |
| Belshaw | Y | | 0.2 | 0.5 | 53°32′38″N 0°50′31″W﻿ / ﻿53.544°N 0.842°W﻿ / 53.544; -0.842﻿ (Belshaw) SE768059 | 1988 | | Map |
| Benniworth Haven Cuttings | | Y | 2.4 | 5.9 | 53°19′26″N 0°09′43″W﻿ / ﻿53.324°N 0.162°W﻿ / 53.324; -0.162﻿ (Benniworth Haven Cuttings) TF225824 | 1966 | GCR | Map |
| Bratoft Meadows | Y | | 2.3 | 5.6 | 53°09′07″N 0°13′05″E﻿ / ﻿53.152°N 0.218°E﻿ / 53.152; 0.218﻿ (Bratoft Meadows) TF484639 | 1968 | WT, NCR | Map |
| Broughton Alder Wood | Y | | 0.8 | 2 | 53°34′37″N 0°33′07″W﻿ / ﻿53.577°N 0.552°W﻿ / 53.577; -0.552﻿ (Broughton Alder Wood) SE960099 | 1986 | | Map |
| Broughton Far Wood | Y | | 17.8 | 44 | 53°34′59″N 0°33′04″W﻿ / ﻿53.583°N 0.551°W﻿ / 53.583; -0.551﻿ (Broughton Far Wood) SE960106 | 1957 | | Map |
| Calceby Marsh | Y | | 8.8 | 21.8 | 53°16′23″N 0°05′38″E﻿ / ﻿53.273°N 0.094°E﻿ / 53.273; 0.094﻿ (Calceby Marsh) TF397772 | 1970 | WT, NCR | Map |
| Candlesby Hill Quarry | Y | | 1.8 | 4.5 | 53°11′28″N 0°11′02″E﻿ / ﻿53.191°N 0.184°E﻿ / 53.191; 0.184﻿ (Candlesby Hill) TF460682 | 1966 | WT | Map |
| Castle Bytham Quarry | | Y | 5.5 | 13.6 | 52°45′00″N 0°32′10″W﻿ / ﻿52.75°N 0.536°W﻿ / 52.75; -0.536﻿ (Castle Bytham Quarry) SK989179 | 1981 | GCR | Map |
| Castlethorpe Tufas | | Y | 0.5 | 1.3 | 53°33′25″N 0°31′30″W﻿ / ﻿53.557°N 0.525°W﻿ / 53.557; -0.525﻿ (Castlethorpe Tufas) SE978077 | 1989 | GCR | Map |
| Chapel Point-wolla Bank | | Y | 39.7 | 98.0 | 53°14′31″N 0°20′10″E﻿ / ﻿53.242°N 0.336°E﻿ / 53.242; 0.336﻿ (Chapel Point-Wolla Bank) TF560742 | 2002 | GCR | Map |
| Claxby Chalk Pit | Y | Y | 2.2 | 5.5 | 53°13′23″N 0°10′12″E﻿ / ﻿53.223°N 0.17°E﻿ / 53.223; 0.17﻿ (Claxby Chalk Pit) TF450717 | 1968 | GCR, WT | Map |
| Cleatham Quarry | Y | | 5.8 | 14.2 | 53°30′04″N 0°35′02″W﻿ / ﻿53.501°N 0.584°W﻿ / 53.501; -0.584﻿ (Cleatham Quarry) SE940014 | 1986 | | Map |
| Cliff Farm Pit | | Y | 1.1 | 2.8 | 53°29′42″N 0°34′59″W﻿ / ﻿53.495°N 0.583°W﻿ / 53.495; -0.583﻿ (Cliff Farm Pit) SE941008 | 1985 | GCR | Map |
| Cliff House | Y | | 4.8 | 11.7 | 53°26′46″N 0°32′56″W﻿ / ﻿53.446°N 0.549°W﻿ / 53.446; -0.549﻿ (Cliff House) SK965953 | 1966 | | Map |
| Copper Hill | | Y | 6.6 | 16.4 | 52°58′19″N 0°32′42″W﻿ / ﻿52.972°N 0.545°W﻿ / 52.972; -0.545﻿ (Copper Hill) SK978426 | 1950 | GCR | Map |
| Conesby (Yorkshire East) Quarry | | Y | 0.9 | 2.2 | 53°37′19″N 0°38′10″W﻿ / ﻿53.622°N 0.636°W﻿ / 53.622; -0.636﻿ (Conesby (Yorkshire East) Quarry) SE903148 | 1995 | GCR | Map |
| Cowbit Wash | | Y | 9.1 | 22.4 | 52°45′18″N 0°09′50″W﻿ / ﻿52.755°N 0.164°W﻿ / 52.755; -0.164﻿ (Cowbit Wash) TF240191 | 1999 | GCR | Map |
| Cross Drain | Y | | 5.7 | 14.2 | 52°42′32″N 0°17′02″W﻿ / ﻿52.709°N 0.284°W﻿ / 52.709; -0.284﻿ (Cross Drain) TF160137 | 1991 | | Map |
| Crowle Borrow Pits | Y | | 4.9 | 12.2 | 53°35′10″N 0°48′29″W﻿ / ﻿53.586°N 0.808°W﻿ / 53.586; -0.808﻿ (Crowle Borrow Pits) SE790106 | 1986 | | Map |
| Dalby Hill | | Y | 0.2 | 0.5 | 53°12′14″N 0°06′25″E﻿ / ﻿53.204°N 0.107°E﻿ / 53.204; 0.107﻿ (Dalby Hill) TF408695 | 1986 | GCR | Map |
| Deeping Gravel Pits | Y | | 57.6 | 142.3 | 52°39′32″N 0°15′36″W﻿ / ﻿52.659°N 0.26°W﻿ / 52.659; -0.26﻿ (Deeping Gravel Pits) TF178082 | 1968 | Wildlife refuge | Map |
| Doddington Clay Woods | Y | | 23.9 | 59.0 | 53°13′41″N 0°39′07″W﻿ / ﻿53.228°N 0.652°W﻿ / 53.228; -0.652﻿ (Doddington Clay Woods) SK901710 | 1987 | | Map |
| Dole Wood | Y | | 4.0 | 9.8 | 52°43′55″N 0°23′10″W﻿ / ﻿52.732°N 0.386°W﻿ / 52.732; -0.386﻿ (Dole Wood) TF091161 | 1968 | WT | Map |
| Dunsby Wood | Y | | 54.6 | 134.8 | 52°49′12″N 0°23′06″W﻿ / ﻿52.82°N 0.385°W﻿ / 52.82; -0.385﻿ (Dunsby Wood) TF089259 | 1968 | | Map |
| Eastoft Meadow | Y | | 0.8 | 2.1 | 53°37′05″N 0°48′47″W﻿ / ﻿53.618°N 0.813°W﻿ / 53.618; -0.813﻿ (Eastoft Meadow) SE786142 | 1985 | | Map |
| Epworth Turbary | Y | | 32.9 | 81.3 | 53°31′34″N 0°51′50″W﻿ / ﻿53.526°N 0.864°W﻿ / 53.526; -0.864﻿ (Epworth Turbary) SE754039 | 1951 | WT | Map |
| Fulsby Wood | Y | | 109.3 | 270.0 | 53°08′02″N 0°07′26″W﻿ / ﻿53.134°N 0.124°W﻿ / 53.134; -0.124﻿ (Fulsby Wood) TF256613 | 1986 | | Map |
| Gibraltar Point | Y | | 598.2 | 1,478.3 | 53°06′11″N 0°19′59″E﻿ / ﻿53.103°N 0.333°E﻿ / 53.103; 0.333﻿ (Gibraltar Point) TF563587 | 1951 | Bird sanctuary, SPA, GCR, LNR, WT, NNR, NCR, Ramsar site, SAC | Map |
| Gosling's Corner | Y | | 10.2 | 25.1 | 53°15′43″N 0°17′20″W﻿ / ﻿53.262°N 0.289°W﻿ / 53.262; -0.289﻿ (Gosling'S Corner) TF142752 | 1988 | | Map |
| Great Casterton Road Banks | Y | | 0.4 | 1 | 52°39′47″N 0°30′54″W﻿ / ﻿52.663°N 0.515°W﻿ / 52.663; -0.515﻿ (Great Casterton Road Banks) TF005083 | 1959 | WT | Map |
| Greetwell Hollow Quarry | | Y | 59.3 | 146.6 | 53°14′10″N 0°29′49″W﻿ / ﻿53.236°N 0.497°W﻿ / 53.236; -0.497﻿ (Greetwell Hollow Quarry) TF004721 | 1951 | GCR | Map |
| Grimsthorpe Park | Y | | 116.4 | 287.7 | 52°45′47″N 0°29′13″W﻿ / ﻿52.763°N 0.487°W﻿ / 52.763; -0.487﻿ (Grimsthorpe Park) TF022194 | 1969 | SAC, | Map |
| Hainton Sheepwalk | Y | | 2.5 | 6.3 | 53°21′32″N 0°13′19″W﻿ / ﻿53.359°N 0.222°W﻿ / 53.359; -0.222﻿ (Hainton Sheepwalk) TF184861 | 1989 | | Map |
| Harrington Hall Sand Pit | | Y | 0.1 | 0.2 | 53°13′37″N 0°02′13″E﻿ / ﻿53.227°N 0.037°E﻿ / 53.227; 0.037﻿ (Harrington Hall Sand Pit) TF361719 | 1986 | GCR | Map |
| Hatfield Chase Ditches | Y | | 44.2 | 109.2 | 53°32′31″N 0°53′17″W﻿ / ﻿53.542°N 0.888°W﻿ / 53.542; -0.888﻿ (Hatfield Chase Ditches) SE738056 | 1999 | | Map |
| Haxey Grange Fen | Y | | 13.3 | 32.8 | 53°27′58″N 0°53′24″W﻿ / ﻿53.466°N 0.89°W﻿ / 53.466; -0.89﻿ (Haxey Grange Fen) SK738972 | 1988 | | Map |
| Haxey Turbary | Y | | 14.4 | 35.6 | 53°30′29″N 0°52′26″W﻿ / ﻿53.508°N 0.874°W﻿ / 53.508; -0.874﻿ (Haxey Turbary) SE748018 | 1951 | WT | Map |
| Hewson's Field | Y | | 0.5 | 1.2 | 53°29′10″N 0°49′05″W﻿ / ﻿53.486°N 0.818°W﻿ / 53.486; -0.818﻿ (Hewson'S Field) SK785995 | 1991 | | Map |
| High Barn, Oxcombe | Y | | 8.3 | 20.4 | 53°16′16″N 0°01′16″W﻿ / ﻿53.271°N 0.021°W﻿ / 53.271; -0.021﻿ (High Barn, Oxcombe) TF321767 | 1966 | | Map |
| High Dyke | Y | | 6.8 | 16.7 | 53°02′28″N 0°31′30″W﻿ / ﻿53.041°N 0.525°W﻿ / 53.041; -0.525﻿ (High Dyke) SK990503 | 1951 | | Map |
| Holywell Banks | Y | | 6.1 | 15.1 | 52°43′48″N 0°31′44″W﻿ / ﻿52.73°N 0.529°W﻿ / 52.73; -0.529﻿ (Holywell Banks) SK994157 | 1951 | | Map |
| Honington Camp | Y | | 1.4 | 3.5 | 52°58′12″N 0°34′52″W﻿ / ﻿52.97°N 0.581°W﻿ / 52.97; -0.581﻿ (Honington Camp) SK954423 | 1968 | SAM | Map |
| Hoplands Wood | Y | | 14.2 | 35.0 | 53°13′16″N 0°11′02″E﻿ / ﻿53.221°N 0.184°E﻿ / 53.221; 0.184﻿ (Hoplands Wood) TF459715 | 1966 | WT | Map |
| Horbling Fen | | Y | 15.1 | 37.3 | 52°54′07″N 0°17′24″W﻿ / ﻿52.902°N 0.29°W﻿ / 52.902; -0.29﻿ (Horbling Fen) TF151352 | 1999 | GCR | Map |
| Humber Estuary | Y | Y | 37,000.6 | 91,430.5 | 53°34′41″N 0°01′48″E﻿ / ﻿53.578°N 0.03°E﻿ / 53.578; 0.03﻿ (Humber Estuary) TA345110 | 2004 | SPA, GCR, MOD, NNR, Ramsar site, SAC | Map |
| Hundleby Clay Pit | | Y | 0.8 | 1.9 | 53°10′23″N 0°03′58″E﻿ / ﻿53.173°N 0.066°E﻿ / 53.173; 0.066﻿ (Hundleby Clay Pit) TF382660 | 1986 | GCR, | Map |
| Jenkins Carr | Y | | 3.7 | 9.1 | 53°09′22″N 0°04′23″E﻿ / ﻿53.156°N 0.073°E﻿ / 53.156; 0.073﻿ (Jenkins Carr) TF387641 | 1966 | | Map |
| Keal Carr | Y | | 9.4 | 23.1 | 53°09′43″N 0°03′58″E﻿ / ﻿53.162°N 0.066°E﻿ / 53.162; 0.066﻿ (Keal Carr) TF382648 | 1968 | WT | Map |
| Kingerby Beck Meadows | Y | | 5.5 | 13.6 | 53°25′41″N 0°25′05″W﻿ / ﻿53.428°N 0.418°W﻿ / 53.428; -0.418﻿ (Kingerby Beck Meadows) TF052935 | 1988 | | Map |
| Kirkby Moor | Y | | 73.6 | 181.9 | 53°08′38″N 0°10′12″W﻿ / ﻿53.144°N 0.17°W﻿ / 53.144; -0.17﻿ (Kirkby Moor) TF225623 | 1966 | WT, | Map |
| Kirmington Pits | | Y | 9.1 | 22.5 | 53°35′20″N 0°20′06″W﻿ / ﻿53.589°N 0.335°W﻿ / 53.589; -0.335﻿ (Kirmington Pits) TA103116 | 1951 | GCR | Map |
| Kirton Wood, Lincolnshire | Y | | 30.3 | 74.9 | 52°52′55″N 0°32′42″W﻿ / ﻿52.882°N 0.545°W﻿ / 52.882; -0.545﻿ (Kirton Wood, Lincolnshire) SK980326 | 1968 | NCR | Map |
| Langtoft Gravel Pits | Y | | 28.4 | 70.3 | 52°41′02″N 0°21′22″W﻿ / ﻿52.684°N 0.356°W﻿ / 52.684; -0.356﻿ (Langtoft Gravel Pits) TF112109 | 1968 | | Map |
| Laughton Common | Y | | 54.7 | 135.2 | 53°27′36″N 0°44′28″W﻿ / ﻿53.46°N 0.741°W﻿ / 53.46; -0.741﻿ (Laughton Common) SK837967 | 1999 | | Map |
| Lea Marsh | Y | | 27.6 | 68.1 | 53°22′26″N 0°46′19″W﻿ / ﻿53.374°N 0.772°W﻿ / 53.374; -0.772﻿ (Lea Marsh) SK818870 | 1998 | | Map |
| Linwood Warren | Y | | 25.7 | 63.5 | 53°22′19″N 0°18′07″W﻿ / ﻿53.372°N 0.302°W﻿ / 53.372; -0.302﻿ (Linwood Warren) TF131875 | 1966 | WT | Map |
| Little Scrubbs Meadow | Y | | 2.0 | 4.9 | 53°15′11″N 0°17′02″W﻿ / ﻿53.253°N 0.284°W﻿ / 53.253; -0.284﻿ (Little Scrubbs Meadow) TF146743 | 1988 | WT | Map |
| Manton and Twigmoor | Y | | 88.9 | 219.6 | 53°31′34″N 0°34′59″W﻿ / ﻿53.526°N 0.583°W﻿ / 53.526; -0.583﻿ (Manton and Twigmoor) SE940042 | 1951 | | Map |
| Manton Stone Quarry | | Y | 17.5 | 43.2 | 53°30′36″N 0°35′02″W﻿ / ﻿53.51°N 0.584°W﻿ / 53.51; -0.584﻿ (Manton Stone Quarry) SE940024 | 1986 | GCR | Map |
| Math And Elsea Wood | Y | | 44.2 | 109.3 | 52°45′04″N 0°22′34″W﻿ / ﻿52.751°N 0.376°W﻿ / 52.751; -0.376﻿ (Math And Elsea Wood) TF097183 | 1988 | | Map |
| Mavis Enderby Valley | Y | | 15.7 | 38.8 | 53°10′52″N 0°02′17″E﻿ / ﻿53.181°N 0.038°E﻿ / 53.181; 0.038﻿ (Mavis Enderby Valley) TF363668 | 1988 | | Map |
| Messingham Heath | Y | | 17.8 | 43.9 | 53°31′08″N 0°40′55″W﻿ / ﻿53.519°N 0.682°W﻿ / 53.519; -0.682﻿ (Messingham Heath) SE875033 | 1965 | | Map |
| Messingham Sand Quarry | Y | | 51.8 | 128 | 53°31′12″N 0°37′34″W﻿ / ﻿53.52°N 0.626°W﻿ / 53.52; -0.626﻿ (Messingham Sand Quarry) SE912035 | 1987 | WT | Map |
| Metheringham Heath Quarry | | Y | 12.8 | 31.5 | 53°08′24″N 0°25′37″W﻿ / ﻿53.14°N 0.427°W﻿ / 53.14; -0.427﻿ (Metheringham Heath Quarry) TF053615 | 1981 | GCR | Map |
| Moor Closes | Y | | 6.8 | 16.8 | 52°58′59″N 0°32′31″W﻿ / ﻿52.983°N 0.542°W﻿ / 52.983; -0.542﻿ (Moor Closes) SK980438 | 1968 | WT, NCR, | Map |
| Moor Farm | Y | | 47.0 | 116.1 | 53°09′25″N 0°10′30″W﻿ / ﻿53.157°N 0.175°W﻿ / 53.157; -0.175﻿ (Moor Farm) TF221638 | 1981 | WT | Map |
| Muckton Wood | Y | | 16.7 | 41.3 | 53°18′32″N 0°04′16″E﻿ / ﻿53.309°N 0.071°E﻿ / 53.309; 0.071﻿ (Muckton Wood) TF381811 | 1953 | WT | Map |
| Nettleton Chalk Pit | | Y | 8.1 | 20.0 | 53°28′05″N 0°18′25″W﻿ / ﻿53.468°N 0.307°W﻿ / 53.468; -0.307﻿ (Nettleton Chalk Pit) TF125981 | 1968 | GCR | Map |
| New England Valley | Y | | 6.3 | 15.7 | 53°14′31″N 0°00′04″E﻿ / ﻿53.242°N 0.001°E﻿ / 53.242; 0.001﻿ (New England Valley) TF336735 | 1966 | | Map |
| Normanby Meadow | Y | | 4.2 | 10.3 | 53°23′28″N 0°27′32″W﻿ / ﻿53.391°N 0.459°W﻿ / 53.391; -0.459﻿ (Normanby Meadow) TF026893 | 2002 | | Map |
| North Killingholme Haven Pits | Y | | 21.6 | 53.4 | 53°39′40″N 0°14′13″W﻿ / ﻿53.661°N 0.237°W﻿ / 53.661; -0.237﻿ (North Killingholme Haven Pits) TA166197 | 1996 | WT, SPA | Map |
| Porter's Lodge Meadows | Y | | 9.6 | 23.8 | 52°45′54″N 0°34′37″W﻿ / ﻿52.765°N 0.577°W﻿ / 52.765; -0.577﻿ (Porter'S Lodge Meadows) SK961196 | 1988 | | Map |
| Potterhanworth Wood | Y | | 33.1 | 81.7 | 53°11′17″N 0°23′49″W﻿ / ﻿53.188°N 0.397°W﻿ / 53.188; -0.397﻿ (Potterhanworth Wood) TF072668 | 1968 | Forest nature reserve, NCR | Map |
| Red Hill | Y | | 3.0 | 7.5 | 53°18′29″N 0°06′14″W﻿ / ﻿53.308°N 0.104°W﻿ / 53.308; -0.104﻿ (Red Hill) TF264807 | 1951 | LNR, WT, | Map |
| Robert's Field | Y | | 3.0 | 7.5 | 52°43′23″N 0°31′15″W﻿ / ﻿52.723°N 0.5208°W﻿ / 52.723; -0.5208﻿ (Robert's Field) TF000150 | | LNR, WT, | |
| Risby Warren | Y | Y | 157.1 | 388.2 | 53°36′36″N 0°36′32″W﻿ / ﻿53.61°N 0.609°W﻿ / 53.61; -0.609﻿ (Risby Warren) SE921135 | 1966 | GCR, NCR, | Map |
| Rush Furlong | Y | | 0.5 | 1.2 | 53°29′42″N 0°49′34″W﻿ / ﻿53.495°N 0.826°W﻿ / 53.495; -0.826﻿ (Rush Furlong) SE780004 | 1985 | WT | Map |
| Ryhall Pasture and Little Warren Verges | Y | | 6.2 | 15.4 | 52°42′43″N 0°29′42″W﻿ / ﻿52.712°N 0.495°W﻿ / 52.712; -0.495﻿ (Ryhall Pasture And Little Warren Verges) TF018138 | 1983 | | Map |
| Saltfleetby-Theddlethorpe Dunes National Nature Reserve | Y | | 971.9 | 2,401.5 | 53°23′56″N 0°13′30″E﻿ / ﻿53.399°N 0.225°E﻿ / 53.399; 0.225﻿ (Saltfleetby - Theddlethorpe Dunes) TF480914 | 1951 | NNR, NCR, SAC | Map |
| Sapperton & Pickworth Woods | Y | | 28.1 | 69.3 | 52°53′42″N 0°28′19″W﻿ / ﻿52.895°N 0.472°W﻿ / 52.895; -0.472﻿ (Sapperton & Pickworth Woods) TF029342 | 1968 | | Map |
| Scotton And Laughton Forest Ponds | Y | | 48.3 | 119.4 | 53°28′59″N 0°42′22″W﻿ / ﻿53.483°N 0.706°W﻿ / 53.483; -0.706﻿ (Scotton And Laughton Forest Ponds) SK860992 | 1959 | | Map |
| Scotton Beck Fields | Y | | 16.8 | 41.4 | 53°28′44″N 0°40′55″W﻿ / ﻿53.479°N 0.682°W﻿ / 53.479; -0.682﻿ (Scotton Beck Fields) SK876988 | 1987 | | Map |
| Scotton Common | Y | | 15.1 | 37.3 | 53°28′30″N 0°41′31″W﻿ / ﻿53.475°N 0.692°W﻿ / 53.475; -0.692﻿ (Scotton Common) SK869984 | 1951 | WT, | Map |
| Sea Bank Clay Pits | Y | | 16.6 | 40.9 | 53°17′17″N 0°17′49″E﻿ / ﻿53.288°N 0.297°E﻿ / 53.288; 0.297﻿ (Sea Bank Clay Pits) TF532792 | 1959 | WT, | Map |
| Silverines Meadows | Y | | 6.2 | 15.3 | 53°17′28″N 0°06′40″W﻿ / ﻿53.291°N 0.111°W﻿ / 53.291; -0.111﻿ (Silverines Meadows) TF260788 | 1959 | WT | Map |
| Skendleby Psalter Banks | Y | | 0.9 | 2.2 | 53°13′19″N 0°09′18″E﻿ / ﻿53.222°N 0.155°E﻿ / 53.222; 0.155﻿ (Skendleby Psalter Banks) TF440716 | 1966 | WT | Map |
| Sotby Meadows | Y | | 7.2 | 17.8 | 53°17′02″N 0°11′49″W﻿ / ﻿53.284°N 0.197°W﻿ / 53.284; -0.197﻿ (Sotby Meadows) TF203779 | 1981 | WT | Map |
| South Ferriby Chalk Pit | | Y | 85 | 209.9 | 53°40′01″N 0°29′10″W﻿ / ﻿53.667°N 0.486°W﻿ / 53.667; -0.486﻿ (South Ferriby Chalk Pit) TA001200 | 1987 | GCR | Map |
| Surfleet Lows | Y | | 3.4 | 8.5 | 52°50′24″N 0°08′38″W﻿ / ﻿52.84°N 0.144°W﻿ / 52.84; -0.144﻿ (Surfleet Lows) TF251286 | 1968 | WT | Map |
| Swaby Valley | Y | | 3.4 | 8.4 | 53°16′37″N 0°05′06″E﻿ / ﻿53.277°N 0.085°E﻿ / 53.277; 0.085﻿ (Swaby Valley) TF391776 | 1966 | WT | Map |
| Swallow Wold | Y | | 4.3 | 10.6 | 53°31′37″N 0°14′24″W﻿ / ﻿53.527°N 0.24°W﻿ / 53.527; -0.24﻿ (Swallow Wold) TA168048 | 1966 | | Map |
| Swanholme Lakes | Y | | 53.1 | 131.3 | 53°12′18″N 0°35′24″W﻿ / ﻿53.205°N 0.59°W﻿ / 53.205; -0.59﻿ (Swanholme Lakes) SK943685 | 1985 | LNR, NCR | Map |
| Swinstead Valley | Y | | 8.9 | 22.0 | 52°47′N 0°31′W﻿ / ﻿52.79°N 0.51°W﻿ / 52.79; -0.51﻿ (Swinstead Valley) TF006224 | 1989 | | Map |
| Tattershall Carrs | Y | | 26.6 | 65.7 | 53°06′47″N 0°11′06″W﻿ / ﻿53.113°N 0.185°W﻿ / 53.113; -0.185﻿ (Tattershall Carrs) TF216589 | 1968 | | Map |
| Tattershall Old Gravel Pits | Y | | 14.5 | 35.9 | 53°07′08″N 0°12′47″W﻿ / ﻿53.119°N 0.213°W﻿ / 53.119; -0.213﻿ (Tattershall Old Gravel Pits) TF197595 | 1951 | | Map |
| Tetford Wood | Y | | 5.4 | 13.3 | 53°15′47″N 0°00′25″W﻿ / ﻿53.263°N 0.007°W﻿ / 53.263; -0.007﻿ (Tetford Wood) TF330758 | 1951 | | Map |
| Tetney Blow Wells | Y | | 14.7 | 36.4 | 53°29′10″N 0°00′43″W﻿ / ﻿53.486°N 0.012°W﻿ / 53.486; -0.012﻿ (Tetney Blow Wells) TA320006 | 1968 | WT | Map |
| The Hermitage | Y | | 4.4 | 10.9 | 52°49′37″N 0°30′14″W﻿ / ﻿52.827°N 0.504°W﻿ / 52.827; -0.504﻿ (The Hermitage) TF009265 | 1968 | SAM, | Map |
| The Wash | Y | | 62,045.8 | 153,318.5 | 52°56′28″N 0°15′11″E﻿ / ﻿52.941°N 0.253°E﻿ / 52.941; 0.253﻿ (The Wash) TF515405 | 1972 | SPA, WT, NNR, NCR, Ramsar site, RSPB | Map |
| Thorne Crowle and Goole Moors | Y | | 1919 | 4742.1 | 53°37′59″N 0°54′04″W﻿ / ﻿53.633°N 0.901°W﻿ / 53.633; -0.901﻿ (Thorne Crowle and Goole Moors) SE728157 | 1970 | SPA, WT, NNR, NCR, Ramsar site, SAC | Map |
| Tortoiseshell Wood | Y | | 9.3 | 22.9 | 52°46′05″N 0°34′34″W﻿ / ﻿52.768°N 0.576°W﻿ / 52.768; -0.576﻿ (Tortoiseshell Wood) SK962199 | 1987 | WT, NCR | Map |
| Troy Wood | Y | | 91.1 | 225.1 | 53°06′43″N 0°08′17″W﻿ / ﻿53.112°N 0.138°W﻿ / 53.112; -0.138﻿ (Troy Wood) TF247588 | 1951 | | Map |
| Tuetoes Hills | Y | | 12.5 | 30.8 | 53°30′11″N 0°43′44″W﻿ / ﻿53.503°N 0.729°W﻿ / 53.503; -0.729﻿ (Tuetoes Hills) SE844014 | 1999 | | Map |
| Welton-le-wold Old Gravel Pits | | Y | 3.4 | 8.4 | 53°22′37″N 0°04′37″W﻿ / ﻿53.377°N 0.077°W﻿ / 53.377; -0.077﻿ (Welton-Le-Wold Old Gravel Pits) TF280884 | 1986 | GCR | Map |
| Wickenby Wood | Y | | 43.6 | 107.6 | 53°19′48″N 0°22′52″W﻿ / ﻿53.33°N 0.381°W﻿ / 53.33; -0.381﻿ (Wickenby Wood) TF079827 | 1976 | Forest nature reserve, NCR | Map |
| Willoughby Meadow | Y | | 0.5 | 1.3 | 53°13′01″N 0°12′11″E﻿ / ﻿53.217°N 0.203°E﻿ / 53.217; 0.203﻿ (Willoughby Meadow) TF472712 | 1968 | WT | Map |
| Willoughby Wood | Y | | 23.2 | 57.4 | 53°12′47″N 0°11′10″E﻿ / ﻿53.213°N 0.186°E﻿ / 53.213; 0.186﻿ (Willoughby Wood) TF461707 | 1951 | | Map |
| Wilsford & Rauceby Warrens | Y | | 57.4 | 141.9 | 52°58′44″N 0°28′01″W﻿ / ﻿52.979°N 0.467°W﻿ / 52.979; -0.467﻿ (Wilsford & Rauceby Warrens) TF030435 | 1968 | WT | Map |
| Wilsford Heath Quarry | Y | | 16.2 | 40.0 | 52°57′36″N 0°32′02″W﻿ / ﻿52.96°N 0.534°W﻿ / 52.96; -0.534﻿ (Wilsford Heath Quarry) SK986413 | 1968 | | Map |
| Winceby Rectory Pit | | Y | <0.1 | 0.1 | 53°11′49″N 0°01′30″W﻿ / ﻿53.197°N 0.025°W﻿ / 53.197; -0.025﻿ (Winceby Rectory Pit) TF320685 | 1987 | GCR | Map |
| Withcall And South Willingham Tunnels | Y | | 3.8 | 9.4 | 53°19′41″N 0°10′48″W﻿ / ﻿53.328°N 0.18°W﻿ / 53.328; -0.18﻿ (Withcall And South Willingham Tunnels) TF213828 | 2002 | | Map |
| Woodhall Spa Golf Course | Y | | 55.0 | 135.8 | 53°09′43″N 0°11′31″W﻿ / ﻿53.162°N 0.192°W﻿ / 53.162; -0.192﻿ (Woodhall Spa Golf Course) TF210643 | 1969 | | Map |
| Woodnook Valley | Y | | 9.7 | 23.8 | 52°52′48″N 0°36′43″W﻿ / ﻿52.88°N 0.612°W﻿ / 52.88; -0.612﻿ (Woodnook Valley) SK935323 | 1968 | | Map |
| Wrawby Moor | Y | | 18.5 | 45.6 | 53°35′06″N 0°26′38″W﻿ / ﻿53.585°N 0.444°W﻿ / 53.585; -0.444﻿ (Wrawby Moor) TA031109 | 1966 | | Map |