diff --git a/thin-provisioning/thin_rmap.cc b/thin-provisioning/thin_rmap.cc
index 53ccc25..5416d65 100644
--- a/thin-provisioning/thin_rmap.cc
+++ b/thin-provisioning/thin_rmap.cc
@@ -6,7 +6,10 @@
 
 #include "version.h"
 
+#include "persistent-data/data-structures/btree_damage_visitor.h"
 #include "persistent-data/range.h"
+#include "persistent-data/space-maps/core.h"
+#include "thin-provisioning/file_utils.h"
 #include "thin-provisioning/superblock.h"
 #include "thin-provisioning/mapping_tree.h"
 
@@ -16,10 +19,85 @@ using namespace thin_provisioning;
 //----------------------------------------------------------------
 
 namespace {
+	block_manager<>::ptr
+	open_bm(string const &path) {
+		block_address nr_blocks = get_nr_blocks(path);
+		typename block_io<>::mode m = block_io<>::READ_ONLY;
+		return block_manager<>::ptr(new block_manager<>(path, nr_blocks, 1, m));
+	}
+
+	transaction_manager::ptr
+	open_tm(block_manager<>::ptr bm) {
+		space_map::ptr sm(new core_map(bm->get_nr_blocks()));
+		sm->inc(superblock_detail::SUPERBLOCK_LOCATION);
+		transaction_manager::ptr tm(new transaction_manager(bm, sm));
+		return tm;
+	}
+
+	//--------------------------------
+
 	typedef range<block_address> region;
 
+	using namespace mapping_tree_detail;
+
+	class region_visitor {
+	public:
+		region_visitor(vector<region> const &regions)
+			: regions_(regions) {
+		}
+
+		virtual void visit(btree_path const &path, block_time const &bt) {
+			if (in_regions(bt.block_)) {
+				uint32_t thin_dev = path[0];
+				block_address thin_block = path[1];
+
+				cout << "[" << thin_dev
+				     << ", " << thin_block
+				     << "] -> " << bt.block_
+				     << endl;
+			}
+		}
+
+	private:
+		// Slow, but I suspect we wont run with many regions.
+		bool in_regions(block_address b) const {
+			for (region const &r : regions_)
+				if (r.contains(b))
+					return true;
+
+			return false;
+		}
+
+		vector<region> const &regions_;
+	};
+
+	class damage_visitor {
+	public:
+		virtual void visit(btree_path const &path, btree_detail::damage const &d) {
+			throw std::runtime_error("damage in mapping tree, please run thin_check");
+		}
+	};
+
 	int rmap(string const &path, vector<region> const &regions) {
-		cerr << "Not implemented" << endl;
+		block_counter counter; // FIXME: get rid of this counter arg
+		region_visitor rv(regions);
+		damage_visitor dv;
+
+		try {
+			block_manager<>::ptr bm = open_bm(path);
+			transaction_manager::ptr tm = open_tm(bm);
+
+			superblock_detail::superblock sb = read_superblock(bm);
+			mapping_tree mtree(tm, sb.data_mapping_root_,
+					   mapping_tree_detail::block_traits::ref_counter(tm->get_sm()));
+
+			btree_visit_values(mtree, counter, rv, dv);
+
+		} catch (std::exception const &e) {
+			cerr << e.what();
+			return 1;
+		}
+
 		return 0;
 	}