As we approached, a queue of boats formed to go up. There are 11 locks spread over 1 ½ miles. At the time no boats were coming down so every lock had to be emptied to go up. At about the half way point boats were coming down thus not wasting water. However one boat had stopped for lunch much to the annoyance to those coming up because the lock gate had been left open for them! Ideally a boat goes down with a lock full of water in to the next lock. The delay caused a queue of boats to form. There is really no advantage because each lock can only take one boat up or down. It's a bit like getting 'grid locked' in traffic on the roads. Thankfully there was enough water coming down to keep all the boats afloat in that short pound! We eventually got to the top in 4 hours and luckily it was a nice sunny day. When locking up or down you get to know many people.