Delivering Data: A Real-World Dataset for Last-Mile Delivery Optimization

The dataset captures approximately one month of pharmaceutical delivery operations from a 3PL provider. It represents a Capacitated Vehicle Routing Problem with Time Windows (CVRPTW), incorporating real-world constraints like vehicle capacity, delivery time windows, and operational limits. With nine daily instances covering two delivery days per week, it reflects four to five weeks of routing challenges, providing a benchmark for optimizing last-mile pharmaceutical logistics. 

The dataset is organized into four main folders:

1. Time and Distance Matrices:

This folder contains travel distances and estimated travel times between delivery nodes for each of the nine days. To maintain confidentiality, exact node locations are not provided.

• Distance Matrices: Provide the pairwise distances (in kilometers) between delivery locations

• Time Matrices: Represent travel durations (in minutes) under three different traffic conditions:

• Optimistic: Best-case scenario with minimal traffic 

• Most Likely: Expected travel time 

• Pessimistic: Worst-case scenario with heavy traffic delays

Each dataset version (1-9) has four corresponding Excel files:

1. distance_matrix_X.xlsx

2. time_matrix_mostlikely_X.xlsx

3. time_matrix_optimistic_X.xlsx

4. time_matrix_pessimistic_X.xlsx

where X represents the dataset number (1-9).

2. Order Characteristics:

This folder contains detailed information about daily delivery requests. It includes an Excel file (orders.xlsx) with nine sheets, each corresponding to a specific day's delivery requests. Each order is defined by the following attributes:

• NODE_ID: Unique identifier for each delivery request
• WEIGHT: Weight of the shipment (kg)
• VOLUME: Volume of the shipment (cubic meters)
• SERVICE_TIME: Time required to complete the delivery (minutes)
• EAT: Earliest Arrival Time allowed for delivery
• LAT: Latest Arrival Time allowed for delivery
• TIME_WINDOW: Allowed delivery time window, defined by the EAT and LAT

3. Sector Grouping of Delivery Points

This folder includes daily maps visualizing delivery points grouped by regional units in the Attica region. It focuses on four primary zones: Central Athens, West Athens, North Athens, and East Athens, while also including South Athens and Piraeus (which consistently have zero deliveries) for completeness. 

• Each map shows the spatial distribution and count of deliveries per regional unit.
• Maps are included for each daily instance.
• A bar chart summarizes delivery activity across all nine days. 

4. Heatmaps of Travel Time Variability

This folder provides interpretive heatmaps showing travel time variability across all origin-destination pairs per day. These are based on the optimistic, most likely, and pessimistic time matrices.

• Variability is modeled using a Beta distribution, estimating standard deviation in travel time (minutes).
• One heatmap per day visualizes uncertainty and highlights potentially unstable routes.
• Heatmaps are provided as standalone image files to support qualitative analysis.

Additional Material

The PDF of the published journal article in Data in Brief is attached to this Zenodo record for reference.