diff --git a/cpu/atmega_common/include/architecture_arch.h b/cpu/atmega_common/include/architecture_arch.h
new file mode 100644
index 0000000000..701fa68df1
--- /dev/null
+++ b/cpu/atmega_common/include/architecture_arch.h
@@ -0,0 +1,37 @@
+/*
+ * Copyright (C) 2020 Otto-von-Guericke-Universität Magdeburg
+ *
+ * This file is subject to the terms and conditions of the GNU Lesser
+ * General Public License v2.1. See the file LICENSE in the top level
+ * directory for more details.
+ */
+
+/**
+ * @ingroup     cpu_atmega_common
+ * @{
+ *
+ * @file
+ * @brief       Architecture details
+ *
+ * @author      Marian Buschsieweke <marian.buschsieweke@ovgu.de>
+ *
+ */
+
+#ifndef ARCHITECTURE_ARCH_H
+#define ARCHITECTURE_ARCH_H
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+/* Doc is provided centrally in platform.h, hide this from Doxygen */
+#ifndef DOXYGEN
+#define ARCHITECTURE_WORD_BITS      (8U)
+#endif /* DOXYGEN */
+
+#ifdef __cplusplus
+}
+#endif
+
+/** @} */
+#endif /* ARCHITECTURE_ARCH_H */