What building materials were used to build Roman circuses? How much did it cost to build a circus? Did I have the same cost in all parts of the empire?

The spectacular circuses, with their seating over 250.000 spectators, make them some of the largest sporting venues of all time. Yet their large dimensions represent a potential challenge to offer a representative data set because they better reflect economic trends. They are therefore indicative of economic performance because they demonstrate a willingness of the local elites to invest, through munificentia, in the growth of cities trying to simulate the "shape" of the Circus with typically local characteristics. The choice of building materials depended on many factors: traditions, fashion, climate, and the resources offered by the environment of the respective era.

Economic history studies have traditionally relied mainly on literary sources and the analysis of the production of certain materials and in recent years there have been numerous publications focusing on the study of the cost and work processes of various construction (e.g. Abrams 1989, DeLaine 1997) in architectural energetics, to generates estimates of the amount of work and time dedicated to the construction of monuments.

What interdisciplinary methods have been successfully involved in researching building materials and techniques? Which type of interdisciplinary collaboration provides the best way to study building materials? By answering these questions, the research proposed in this work is an ongoing interdisciplinary project. It has a multilevel approach, involving socio-economic studies, and architectural energy, using digital tools and Machine Learning applied to archaeology.

This paper aims to quantify the construction costs of circuses, starting by calculating the construction elements using a digital and interdisciplinary approach.

The methods used are: a) deconstructing buildings into measurable components and quantifying them using new Blender tools. b) quantifying the number of bricks of a portion of the circus using new tools for classification, such as Machine Learning applied to archaeology (Dininno 2016; Dininno 2017; Grilli et al. 2018), c) estimating volumes and materials used in ancient buildings through architectural energetics in archaeology.

This paper will present the results of a pilot project that focuses on one case study, the Circus of Maxentius in Rome, to be continued with 4 other circuses in the Roman Empire.

The remains of the cavea and part of the well-preserved carceres and traces of the spina make it the best example of a preserved Roman circus and a perfect case study to calculate the construction costs.

The economic data obtained will allow us to compare the economic dynamics of the Empire's different provinces and evaluate the resilience and identity phenomena of the Roman provinces.