Started with an initial Conv2d layer, progressively increasing filters while maintaining 3x3 kernels. ReLU activations and BatchNorm layers were added for non-linearity and normalization. MaxPooling layers were used to downsample the feature maps. Dropout was used to prevent overfitting.
Chose ResNet-18 due to its proven performance and efficiency in various image classification tasks. Since ResNet18 was trained for the ImageNet task, it is a good choice for landmark classification tasks.