To make the main spice blend: Mix together the whole fennel seeds, caraway seeds, celery seeds, and Urfa.
To prepare the fennel: Put the fennel wedges in a large bowl, drizzle with enough oil to evenly coat, and sprinkle with the main spice blend and a generous pinch of salt. Toss to coat.
Heat a 12-inch skillet over high heat for a minute. Add the fennel in a single layer, arranging the wedges in tight concentric circles, leaving no space between the pieces (reserve the bowl that held the spiced fennel). Reduce the heat to medium-high and cook until the fennel is deeply browned in spots but not burned, about 3 minutes.
Use tongs or a small offset spatula to flip all the fennel wedges and cook until the bottoms are browned, about 5 minutes. Flip the pieces again and reduce the heat to medium. Cook, flipping the pieces and rotating the skillet as needed to redistribute hot spots and prevent any burning, until the fennel wedges are evenly browned, about 2 minutes. Return the fennel to the reserved bowl.
Add enough oil to the skillet to coat the bottom (about 2 tablespoons) and place the orange wedges in a single layer, spacing them apart. Reduce the heat to medium and cook, turning once, until browned, about 2 minutes per side. Transfer to a plate.
Quickly return the fennel to the skillet, arranging it in the same tight concentric-circle pattern. Fit the orange between the fennel in concentric circles. Add ¼ cup water to the bowl that held the fennel and then pour it into the skillet along with any spices and accumulated juices.
Scatter the raisins on top, then add the lemon juice and sprinkle with the vinegar. Cover and adjust the heat to maintain a low simmer, turning the fennel and orange slices just once as they cook, until the fennel is tender with just a little bite and has an even caramel color, about 15 minutes. Uncover, remove the pan from the heat, and serve hot, warm, or at room temperature.
To make ahead: The pan-braised fennel can be refrigerated for up to 1 week.