DRILLINGATELCAPITANCONFIRMSPOTENTIALFORABULKTONNAGE,LOWGRADEGOLDDEPOSIT

VANCOUVER,BC(October24,2011)–ManagementofSierraMadreDevelopmentsInc.(“SierraMadre”)(TSX‐V:SMG)andRiversideResourcesLtd.(“Riverside”)(TSX‐V:RRI)arepleasedtoannounceresultsoftherecentlycompleteddrillprogramattheElCapitanTarget,PenolesProject,DurangoState,Mexico.Atotalof2,220metersofHQcoredrillingwascompletedin18drillholes.TheElCapitanTargetisconsideredanadvanced,bulktonnageoxidegoldprospect.PreviouswidelyspaceddrillingatElCapitan(3holescompletedbyAurcanain2004and5holescompletedbyRiversidein2008)intersectedawesttonorthweststriking,30to70meterwidezoneof lowgrade,goldmineralizationthat is intermittentlyexposedforapproximatelyonekilometeralongashallowdipping volcanic – sedimentary contact (the estimated dip of the contact zone is approximately 30 degrees to the south).MineralizedintervalsreportedbyAurcanaandRiversiderangedfrom40.50metersaveraging0.215g/tgold(CDDH08‐05)to61.4metersaveraging0.813g/t(PE04‐01)andincludednarrower,highergradeintervalsrangingfrom7.75metersaveraging0.358g/tto9.80metersaveraging1.067g/t. Themajorityof thehistoricAurcanaandRiversidedrill holeswere spacedat100 to200meterintervalsandtestedthecentralandwesternpartsoftheexposedmineralizedzone,whichisnowreferredtoasthe“MainZone”.Asingle historic hole (CDDH 08‐03) located approximately 500 meters to the east of the “Main Zone” intersected 26.20 metersaveraging0.275g/taswellasnarrowerintervalsofhighergrademineralizationsuggestingpotentialforextensionstothesoutheast(referredtoastheSEExtension).The preliminary geological work by Riverside showed potential for a bulk tonnage, low grade deposit however extensive in‐filldrillingwasrequiredtovalidatetheconceptualmodel.AsannouncedOctober12,2011preliminarymetallurgicaltestscompletedby Inspectorate Exploration andMining Services supports thatmineralization at El Capitan is amenable to low cost, heap leachmining.Theobjectiveofthe2011drillprogramwastovalidatetheconceptualdepositmodel,increasethedensityofpiercepointswithintheMain Zone and test for potential strike extensions of theMain Zone. The recently completed drilling program included 15additionalholesdrilledfrom9separatestationswithintheareareferredtoasthe“MainZone”. Twodrillholes,CDDH11‐04andCDDH11‐11,encounteredpoorgroundconditionsandwerestoppedbeforereachingthetargetzone.Drillstationswerespacedat50to100metersandmostoftheholesweredrilledataninclinationof50degreesalonganazimuthof30degrees(paralleltotheRiversideandAurcanaholes).Twoofthe2011drillstationswerehistoricdrillsitesandthreeofthe2011drillholeswereverticalholes.Theattachedplanviewmapshowsthelocationofallofthe2011andhistoricholesandthefollowingtableslistall2011andhistoricresultsfortheMainZone.MainZoneDrillResultsResultsofthedrillingprogramwereencouraginginthatthegradeandthicknessofmineralizationencounteredinthe“MainZone”showedconsiderable improvementoverpreliminarydrilling resultsreportedbyRiverside in2008. Thestrike lengthofthe “MainZone”wasextendedandseveralofthedrillholesencounteredmineralized intervalswithpotentiallyeconomicgradesinexcessof70meters inthickness includingCDDH11‐07whichreturned108.35metersaveraging0.410g/tandCDDH11‐17whichreturned88.40 meters averaging 0.816 g/t (including 33.50 meters averaging 1.687 g/t).The widths quoted are drilled widths and arebelievedtorepresentapproximatetruewidths.Actualwidthshavenotyetbeencalculated.

SierraMadreCEOCarlvonEinsiedel,P.Geo.commentsthat:Atotalof22drillholes(fifteendrillholesin2011andsevenhistoricdrill holes) have now been completed within the Main Zone. The zone has been traced by drilling over a strike length ofapproximately700metersandappearstobeopenforexpansionalongstriketothewestandnorthwestoftheareathathasbeentestedbydrilling.Onlyalimitedamountofdrillinghasbeencompletedtotestthedowndipextentoftheknownmineralizedzone.IntheopinionoftheCompany,basedontheassayresultsfromthe2011drillholesandthereportedresultsfromthe2004and2008drillholestheElCapitantargetwarrantsadditionaldrilltesting.Table1:MainZone2011DrillHoleSummary Drillhole Inclination From(m) To(m) Interval(m) Aug/t

CDDH‐11‐01 ‐50 90.35 122.50 32.15 0.478includes 105.20 108.90 3.70 1.036 CDDH‐11‐02 ‐50 45.45 96.20 50.75 0.509includes 62.60 77.00 14.40 1.084includes 71.00 75.60 4.60 2.411 CDDH‐11‐03 ‐90 35.35 126.00 90.65 0.603includes 78.75 116.25 37.50 1.030includes 91.50 97.90 6.40 1.902 CDDH‐11‐04 ‐50 Abandoned,PoorGroundConditions

CDDH‐11‐05 .75 2.30 68.80 66.50 0.203includes 14.80 31.75 16.95 0.448

CDDH‐11‐06 ‐50 28.35 79.85 51.50 0.141CDDH‐11‐06 110.75 155.50 44.75 0.182

CDDH‐11‐07 ‐50 57.20 165.55 108.35 0.410includes 57.20 71.15 13.95 0.619includes 90.65 103.70 13.05 0.788

CDDH‐11‐11 ‐50 Abandoned,PoorGroundConditions CDDH‐11‐12 ‐50 13.28 74.2 60.92 0.154CDDH‐11‐12 170.15 194.4 24.25 0.236 CDDH‐11‐13 ‐60 63.15 92.05 28.90 0.469includes 64.85 85.70 20.85 0.502includes 64.85 68.10 3.25 0.918 CDDH‐11‐14 ‐90 77.70 114.80 37.10 0.694includes 90.35 103.00 12.65 1.389includes 94.55 99.60 5.05 2.088 CDDH‐11‐15 ‐50 46.55 74.15 27.60 0.202CDDH‐11‐15 91.80 131.15 39.35 0.217 CDDH‐11‐16 ‐60 42.70 104.00 61.30 0.680includes 61.70 76.10 14.40 1.521includes 69.60 74.00 4.40 2.429 CDDH‐11‐17 ‐90 43.40 131.80 88.40 0.816includes 80.50 114.00 33.50 1.687includes 95.95 104.00 8.05 2.405includes 99.85 104.00 4.15 3.098 CDDH‐11‐18 ‐60 64.05 97.90 33.85 1.399includes 82.35 97.90 15.55 2.096

Note:GoldgradereportedbyInspectorateinppb(partsperbillion).Thegradeing/twascalculatedbydividingthereported grade in ppb by a factor of 1,000. Widths quoted are drilled width. Calculation of true widths arepending.

Table2:MainZoneHistoric2008DrillHoleSummaryasreportedonRiversideResourceswebsite

Drillhole Inclination From(m) To(m) Interval(m) Aug/t

CDDH‐08‐01 ‐60 33.75 35.20 1.45 2.510

CDDH‐08‐01 47.00 76.18 29.18 0.530

includes 61.90 71.70 9.80 1.067

CDDH‐08‐02 ‐50 89.94 122.25 32.31 0.659

includes 102.25 105.30 3.05 1.844

includes 102.25 111.80 9.55 1.114

CDDH‐08‐04 ‐55 182.65 189.50 6.85 0.265

includes 184.10 188.30 4.20 0.343

CDDH‐08‐05 ‐45 71.13 72.65 1.52 0.992

176.50 217.00 40.50 0.215

includes 180.25 188.00 7.75 0.358

Note:GoldgradewasoriginallyreportedbyRiversideinppb(partsperbillion).Thegradeing/twascalculatedbydividingthereportedgradeinppbbyafactorof1000.Widthsquotedaredrilledwidth.Calculationoftruewidthsarepending. Table3:MainZoneHistoric2004DrillHoleSummary

Drillhole Inclination From(m) To(m) Interval(m) Aug/t

PE04‐01 ‐55 31.85 93.27 61.42 0.813

includes 76.20 80.77 4.57 6.400

PE04‐02 ‐55 125.0 190.50 65.5 0.172

PE04‐04 ‐75 78.0 147.52 69.52 0.309

Note:GoldgradewasoriginallyreportedbyRiversideinppb(partsperbillion).Thegradeing/twascalculatedbydividingthereportedgradeinppbbyafactorof1000.Widthsquotedaredrilledwidth.Calculationoftruewidthsarepending.SEExtensionDrillResultsInadditiontothedrilltestingwithintheMainZoneatotaloffourdrillholes(three2011drillholesCDDH‐11‐08,11‐09,11‐10,andonehistoricdrillholeCDDH‐08‐03)havebeencompletedtoteststrikeextensionofthemineralizedzonetothesoutheast(referredtoasthe“SouthEastExtension”).AlthoughresultsareencouragingthegoldgradesandthicknessesencounteredintheSouthEastExtensionarenotconsideredtobeassignificantasthegoldgradesandthicknessesencounteredintheMainZone.

Table4:SEExtensionZoneHistoric2008and2011andDrillHoleSummary

Drillhole Inclination From(m) To(m) Interval(m) Aug/t

CDDH‐08‐03 ‐45 31.05 35.05 4.00 0.860

CDDH‐08‐03 74.60 78.90 4.30 0.724

CDDH‐08‐03 84.80 111.00 26.20 0.275

CDDH‐08‐03 183.05 190.30 7.25 0.443

CDDH‐11‐08 ‐50 NoSignificantResults CDDH‐11‐09 ‐50 19.45 68.95 49.50 0.200 CDDH‐11‐10 ‐50 19.05 76.20 57.15 0.177includes 51.85 76.20 24.35 0.208

SierraMadreCEO,CarlvonEinsiedel,P.Geo.comments:“the2011drillresultsfromElCapitanhaveconfirmedthereispotentialforabulktonnage lowgradegolddepositatElCapitan. ThenextstepforSierraMadrewillbeto continuethedrillingprogramandmetallurgicaltestworkanddelineatetheextentofmineralizationwithintheMainZone.Theabilitytoconductyearround,lowcostdrillingoperationsshouldmakeitpossiblefortheCompanytoadvancetheprojectwithaminimumofshareholderdilution.”QA/QCfortheSierraMadredrillprogramAlldrillcorewasplacedinnumberedboxesandtransportedtoSierraMadre’ssecurecorefacilitiesbythedrillcontractor.Followingdetailed core loggingall corewas splitusingadiamondbladedcore sawunder thedirect supervisionof SierraMadre’sGeologicstaff. Onehalfofcorewaskeptonsite intheoriginal coreboxes,thesecondhalfwasplacedin labeledandsealed samplebagswhichweretransporteddirectlytothecustodyofInspectorateAmericaCorporation(“Inspectorate”),alaboratorycertifiedfortheprovision of assays and geochemical analysis (ISO:9001‐2008). Samples were transported to Inspectorate’s facilities in Durango,Mexico for prepwork and analyzed at their facilities in Reno, Nevada. All samples were prepared using standard industry prepmethods followedby fireassayanalysisandaqua regiadigest for trace elements. All sampleswithgreater than10g/tAuwereadditionallytestedbyfireassaywithagravimetricfinish.SierraMadrehasincluded4%industrycertifiedAustandardsandblankswithin the sample stream inaddition to fieldduplicatesaspartof theQA/QCprogram. Inspectorate includesaminimumof9%certifiedstandardsandduplicateanalysisaspartoftheirlaboratoryprocedures.Additionalgoldmetallicscreenassayswereperformedon85selectsamplestocheckforacoarsegoldcomponent.Sampleswerecrushedto150meshandboththe+150meshand‐150meshportionswereassayedforgold.Theresultsshow70of85samplesinwhich95%ofthetotalgoldispresentinthe‐150meshassay.Onlytwosamplesdisplayresultswheregreaterthan10%oftotalAuispresentinthe+150meshportionoftheassay.CarlvonEinsiedel,P.Geo.,isSierraMadre’sQualifiedPersonwhoreviewedandapprovedthispressrelease.About Sierra Madre Developments and the Penoles Project: Sierra Madre is a recently listed juniormining company based inVancouver, British Columbia, Canada.Management has extensive exploration andmining expertise and the Company’s businessmodel is toacquireadvanced goldand silverprojectsandbuild shareholdervalueby rapidlyadvancingourprojects through theresourcedelineationstage.Pursuant to an agreement signedMarch 4, 2011 with Riverside, SierraMadre has the right to earn up to a 70% interest in thePenoles Project bymaking payments to the underlying owners, incurring staged exploration expenditures and issuing shares instagestoRiverside.InadditiontoElCapitantheprojecthoststwohistoricsilverminesthatwereoperatedinthelate1800’sandahighlyprospective35,000hectarelandpackage.Thereisverylittletechnicaldataavailableregardingtheminesbutitappearstheyhaveneverbeendrilltested.ConcurrentwiththedrillingprogramatElCapitan,extensivebackhoetrenchingwascarriedoutatoneofthehistoricmines(JesusMaria)toassessthethicknessandgradesencounteredinthehistoricminingoperations.OncompletionofthedrillingprogramatElCapitanasingledrillholewascompletedtotestifmineralizationcontinuesatdepthbelowthehistoricmineworkings.Resultsofthetrenchinganddrillingwillbeannouncedastheybecomeavailable.

ONBEHALFOFTHEBOARDOFDIRECTORSSierraMadreDevelopmentsInc.“CarlvonEinsiedel”ChiefExecutiveOfficerandDirectorDrillHoleLocationMap

FORWARD‐LOOKINGSTATEMENTSDISCLAIMER:Certainstatements in thispress releasemay beconsidered forward‐looking information.Thesestatementscanbeidentifiedbytheuseofforward‐lookingterminology(e.g.,"expect”,”estimates", "intends", "anticipates", "believes","plans").Suchinformationinvolvesknownandunknownrisks ‐‐ including theavailabilityof funds, the resultsof financingandexplorationactivities, the interpretationofexploration resultsandothergeologicaldata,orunanticipatedcostsandexpensesandotherrisksidentifiedbySierraMadreinitspublicsecuritiesfilingsthatmaycauseactualeventstodiffermateriallyfromcurrentexpectations.Readersarecautionednottoplaceunduerelianceontheseforward‐lookingstatements,whichspeakonlyasofthedateofthispressrelease.NeithertheTSXVentureExchangenoritsRegulationServicesProvider(asthattermisdefinedinthepoliciesoftheTSXVentureExchange)acceptsresponsibilityfortheadequacyoraccuracyofthisnewsrelease.