diff --git a/libs/libclkarchopenfpga/src/base/clock_network.h b/libs/libclkarchopenfpga/src/base/clock_network.h
new file mode 100644
index 000000000..4ff964182
--- /dev/null
+++ b/libs/libclkarchopenfpga/src/base/clock_network.h
@@ -0,0 +1,108 @@
+#ifndef CLOCK_NETWORK_H
+#define CLOCK_NETWORK_H
+
+/********************************************************************
+ * This file include the declaration of pin constraints
+ *******************************************************************/
+#include <array>
+#include <map>
+#include <string>
+
+/* Headers from vtrutil library */
+#include "vtr_vector.h"
+
+/* Headers from openfpgautil library */
+#include "clock_network_fwd.h"
+#include "openfpga_port.h"
+
+namespace openfpga {  // Begin namespace openfpga
+
+/********************************************************************
+ * A data structure to describe a clock network
+ * A clock network consists of a number of clock trees
+ * each of which has:
+ * - a unique id
+ * - different entry point
+ *
+ * Typical usage:
+ * --------------
+ *   // Create an object of clock network
+ *   ClockNetwork clk_ntwk;
+ *   // Create a new clock tree which contains 8 clock pins
+ *   ClockTreeId clk_tree_id = clk_ntwk.create_tree("tree1")
+ *   // Add a spine to the clock tree
+ *   ClockSpineId clk_spine_id = clk_ntwk.create_spine("tree1_spine0");
+ *
+ *******************************************************************/
+class ClockNetwork {
+ public: /* Types */
+  typedef vtr::vector<ClockTreeId, ClockTreeId>::const_iterator
+   clock_tree_iterator;
+  /* Create range */
+  typedef vtr::Range<clock_tree_iterator> clock_tree_range;
+
+ public: /* Constructors */
+  ClockNetwork();
+
+ public: /* Accessors: aggregates */
+  clock_tree_range trees() const;
+
+ public: /* Public Accessors: Basic data query */
+  /* Find a spine by name, return a valid id if found, otherwise return an invalid id */
+  ClockSpineId spine(const std::string& name) const;
+
+  /* Check if there are clock tree */
+  bool empty() const;
+
+ public: /* Public Mutators */
+  /* Reserve a number of spines to be memory efficent */
+  void reserve_spines(const size_t& num_spines);
+
+  /* Reserve a number of trees to be memory efficent */
+  void reserve_trees(const size_t& num_trees);
+
+  /* Create a new tree, by default the tree can accomodate only 1 clock signal; use width to adjust the size */
+  ClockTreeId create_tree(const std::string& name, const size_t& width = 1);
+
+  /* Create a new spine, if the spine is already created, return an invalid id */
+  ClockSpineId create_spine(const std::string& name);
+
+  /* Set the parent tree for a given spine. It is illegal that a spine which does not belong to any tree */
+  void set_spine_parent_tree(const ClockSpineId& spine, const ClockTreeId& parent_tree);
+  void set_spine_start_point(const ClockSpineId& spine, const vtr::Point<int>& point);
+  void set_spine_end_point(const ClockSpineId& spine, const vtr::Point<int>& point);
+  void add_spine_switch_point(const ClockSpineId& spine, const ClockSpineId& drive_spine, const vtr::Point<int>& coord);
+
+ public: /* Public invalidators/validators */
+  /* Show if the tree id is a valid for data queries */
+  bool valid_tree_id(const ClockTreeId& tree_id) const;
+
+  /* Show if the tree id is a valid for data queries */
+  bool valid_spine_id(const ClockSpineId& spine_id) const;
+
+ private: /* Internal data */
+  /* Basic information of each tree */
+  vtr::vector<ClockTreeId, ClockTreeId> clk_tree_ids_;
+  vtr::vector<ClockTreeId, std::string> clk_tree_names_;
+  vtr::vector<ClockTreeId, std::vector<ClockSpineId>> clk_tree_top_spines_;
+
+  /* Basic information of each spine */
+  vtr::vector<ClockSpineId, ClockSpineId> clk_spines_;
+  vtr::vector<ClockSpineId, std::string> clk_spine_names_;
+  vtr::vector<ClockSpineId, size_t> clk_spine_levels_;
+  vtr::vector<ClockSpineId, vtr::Point<int>> clk_spine_start_points_;
+  vtr::vector<ClockSpineId, vtr::Point<int>> clk_spine_end_points_;
+  vtr::vector<ClockSpineId, std::vector<ClockSpineId>> clk_spine_switch_points_;
+  vtr::vector<ClockSpineId, std::vector<vtr::Point<int>>> clk_spine_switch_coords_;
+  vtr::vector<ClockSpineId, ClockSpineId> clk_spine_parent_;
+  vtr::vector<ClockSpineId, ClockTreeId> clk_spine_parent_tree_;
+
+  /* Fast lookup */
+  std::map<std::string, ClockSpineId> spine_name2ids_;
+
+  /* Flags */
+  bool is_dirty_;
+};
+
+}  // End of namespace openfpga
+#endif
diff --git a/libs/libclkarchopenfpga/src/base/clock_network_fwd.h b/libs/libclkarchopenfpga/src/base/clock_network_fwd.h
new file mode 100644
index 000000000..d936bbb9c
--- /dev/null
+++ b/libs/libclkarchopenfpga/src/base/clock_network_fwd.h
@@ -0,0 +1,28 @@
+/************************************************************************
+ * A header file for ClockNetwork class, including critical data declaration
+ * Please include this file only for using any PinConstraints data structure
+ * Refer to clock_network.h for more details
+ ***********************************************************************/
+
+/************************************************************************
+ * Create strong id for ClockNetwork to avoid illegal type casting
+ ***********************************************************************/
+#ifndef CLOCK_NETWORK_FWD_H
+#define CLOCK_NETWORK_FWD_H
+
+#include "vtr_strong_id.h"
+
+namespace openfpga {  // Begin namespace openfpga
+
+struct clock_tree_id_tag;
+struct clock_spine_id_tag;
+
+typedef vtr::StrongId<clock_tree_id_tag> ClockTreeId;
+typedef vtr::StrongId<clock_spine_id_tag> ClockSpineId;
+
+/* Short declaration of class */
+class ClockNetwork;
+
+}  // End of namespace openfpga
+
+#endif