Wireless communications between a base station and one or more wireless devices are described. Multiple downlink reference signals may correspond to multiple random access resources for a random access procedure. A base station may provide a set of downlink reference signals before a set of physical random access channels (PRACHs) are available for use. A wireless device performing a random access procedure may select two or more random access resource occasions (e.g., PRACH occasions) based on the downlink reference signals. Using a listen before talk (LBT) procedure, the wireless device may select a first available random access resource occasion from the two or more random access resource occasions that are determined to be clear.