diff --git a/src/cpp/ripple/PathDB.cpp b/src/cpp/ripple/PathDB.cpp
new file mode 100644
index 000000000..4c9f8a47d
--- /dev/null
+++ b/src/cpp/ripple/PathDB.cpp
@@ -0,0 +1 @@
+#include "PathDB.h"
diff --git a/src/cpp/ripple/PathDB.h b/src/cpp/ripple/PathDB.h
new file mode 100644
index 000000000..138e78bf6
--- /dev/null
+++ b/src/cpp/ripple/PathDB.h
@@ -0,0 +1,78 @@
+#ifndef PATHDB__H
+#define PATHBD__H
+
+#include "uint256.h"
+#include "TaggedCache.h"
+
+typedef std::pair<uint160, uint160> currencyIssuer_t;
+typedef std::pair<const uint160&, const uint160&> currencyIssuer_ct;
+
+class PathDBEntry
+{
+public:
+	typedef boost::shared_ptr<PathDBEntry>	pointer;
+	typedef const pointer&					ref;
+
+	const unsigned int sIsExchange	= 0x00001;
+	const unsigned int sIsOffer 	= 0x00002;
+	const unsigned int sIsDirty		= 0x10000;
+
+protected:
+	currencyIssuer_t	mIn;
+	currencyIssuer_t	mOut;
+	uint32				mLastSeq;
+	int					mUseCount;
+	unsigned			mFlags;
+	std::size_t			mHash;
+
+public:
+
+	void				updateSeq(uint32);
+
+	const uint160&		getCurrencyIn() const		{ return mIn.first; }
+	const uint160&		getIssuerIn() const			{ return mIn.second; }
+	const uint160&		getCurrencyOut() const		{ return mOut.first; }
+	const uint160&		getIssuerOut() const		{ return mOut.second; }
+
+	bool				isExchange() const;
+	bool				isOffer() const;
+	bool				isDirty() const;
+};
+
+class PathDB
+{
+protected:
+	boost::recursive_mutex						mLock;
+	TaggedCache<currencyIssuer_t, PathDBEntry>	mFromCache;
+	TaggedCache<currencyIssuer_t, PathDBEntry>	mToCache;
+	std::set<PathDBEntry::pointer>				mDirtyPaths;
+
+public:
+
+	PathDB();
+
+	std::vector<PathDBEntry::pointer>	getPathsFrom(const uint160& currency, const uint160& issuer,
+		int maxBestPaths = 10, int maxRandPaths = 10);
+
+	std::vector<PathDBEntry::pointer>	getPathsTo(const uint160& currency, const uint160& issuer,
+		int maxBestPaths = 10, int maxRandPaths = 10);
+
+	void usedLine(const uint160& currency, const uint160& accountIn, const uint160& accountOut);
+	void usedExchange(const uint160& currencyFrom, const uint160& issuerFrom,
+		const uint160& currencyTo, const uint160& issuerTo);
+};
+
+extern std::size_t hash_value(const currencyIssuer_ct& ci)
+{
+	std::size_t r = hash_value(ci.second);
+	return ci.first.hash_combine(r);
+}
+
+static inline std::size_t hash_value(const currencyIssuer_t& ci)
+{
+	std::size_t r = hash_value(ci.second);
+	return ci.first.hash_combine(r);
+}
+
+
+#endif