An arch over the bathtub is a great way to add unique detail to your bathroom. I escpecially love it when the arches are tiled!! You can add a waterproof can light to the top of the arch to highlight this feature. If you want to tile the front of the tub too- you'll need to use a drop in tub with flanges on 3 sides ( the tile will cover the flange on the back and 2 side walls). Take a look at these inspirational examples....