The traveller often regarded as the greatest traveller of pre-modern times, believed to have covered more than 73,000 miles and visited regions equal to about 44 modern countries, is:

Introduction / Context:
This question belongs to world history and historical geography. It asks you to identify the traveller who is often considered the greatest traveller of pre-modern times based on the enormous distances he covered and the number of regions he visited. Such travellers are important sources for our knowledge of medieval societies.

Given Data / Assumptions:

• The traveller is said to have travelled over 73,000 miles.
• He is believed to have visited territories equal to about 44 modern countries.
• Options include Marco Polo, Fa Hien, Ibn Battuta and Hiuen Tsang.
• We assume basic familiarity with these travellers and their routes.

Concept / Approach:
Ibn Battuta was a Moroccan traveller of the 14th century who journeyed extensively across the Islamic world and beyond. His travels took him through North Africa, West Asia, Central Asia, India, Sri Lanka, the Maldives, Southeast Asia and parts of China. Estimates suggest that he travelled more than 73,000 miles in total, far exceeding the distances covered by most other pre-modern travellers. His famous travel account, often known as the Rihla, records observations about many lands and courts, including the Delhi Sultanate under Muhammad bin Tughlaq.

Step-by-Step Solution:
Step 1: Recall that Marco Polo, Ibn Battuta, Fa Hien and Hiuen Tsang are all famous travellers but belonged to different periods and regions.Step 2: Remember that Fa Hien and Hiuen Tsang were mainly Buddhist pilgrims from China who travelled primarily to India and neighbouring regions.Step 3: Marco Polo, a Venetian traveller, journeyed mainly to East and Central Asia, particularly China.Step 4: Ibn Battuta, however, spent decades travelling across a vast area from Africa to China, with total distances estimated at over 73,000 miles.Step 5: Match this record of distance and number of regions with the description in the question and select Ibn Battuta.

Verification / Alternative check:
World history references and many encyclopaedias describe Ibn Battuta as arguably the most widely travelled individual of the pre-modern era. Exam books often mention that he travelled more than any other known medieval traveller, covering more than 70,000 miles. These sources consistently match the numeric details given in the question with Ibn Battuta, not with Marco Polo or the Chinese pilgrims.

Why Other Options Are Wrong:
Marco Polo: A major traveller, but his journeys were fewer and covered a smaller total distance than those of Ibn Battuta.Fa Hien (Faxian): A Buddhist monk who travelled to India for scriptures, but his journeys were more limited in range.Hiuen Tsang (Xuanzang): Another important Chinese pilgrim, but again his travels did not reach the estimated distance and number of regions associated with Ibn Battuta.

Common Pitfalls:
Students sometimes choose Marco Polo simply because his name is very famous in popular culture. Others may confuse Fa Hien and Hiuen Tsang with general records of long travel. To avoid confusion, memorise that Ibn Battuta is the traveller whose journeys are often summarised as more than 73,000 miles covering about 44 modern countries.

Final Answer:
The traveller described as having covered over 73,000 miles and visited regions equal to about 44 modern countries is Ibn Battuta.