The organ at the Sint Bavo church in Haarlem will finally be cleaned of layers of bat droppings deposited there over the years.

The Bavo organ, built by Amsterdam organ builder Christan Müller between 1735 and 1738, was the biggest in the world at the time. It no longer holds that title, the church’s organ player Anton Pauw told NOS radio, but ‘its beautiful casing is still the most imposing ever made’.

The organ’s fame spread far and wide and attracted famous composers like Handel and Mozart to Haarlem. ‘We know Handel came twice, and played on the organ during one visit. Mozart stopped here in 1766 and played the organ for an hour,’ Pauw said.

However, the man who has played the church’s organ for thirty years has had to say goodbye to the instrument for a much-needed restoration which started this week.

‘I’m sorry but not sorry,’ he said. ‘Bats have been making their home here for years and the organ is covered in droppings. It’s incredibly filthy. But worse still, the acid in their urine is eating away at the pipes.’ If holes start to appear, Pauw said, the church will be even deeper in (bat) sh**.

Haarlem local council is financing the restoration, which is expected to take a couple of months.