The study area is Osogbo, Osun State. It is situated at 7°46′ North 4°34′East. It covers approximately 126.0km2. Osogbo is situated northeast of Ibadan, south of Ilorin, and northwest of Akure. It also shares boundaries with Ikirun, Ilesa, Ede, Egbedore, Ogbomoso and Iragbiji. It is centrally located in Osun State and this makes it more easily accessible from any part of the State. It has an elevation of 320m. It has a tropical climate with rainfall (March to November) and the dry season (November to February) and an average annual temperature of 25.50 C (i.e.77.8 degrees Fahrenheit) and 1361 Millimetres (53.6 inches) of precipitation [11]. It is a protected area covered by riparian forest, dry high forest, and derived savannah. The population as of National Population Census, 2006 was 156,694 people. Osogbo is popularly known as the trade center for a farming region with such produce as yams, cassava, maize, cotton, and tobacco. It is also renowned for tie and dye and is called “Home of Tie and Dye” because many traditional tie and dye industries are situated in Osogbo [12]. Osogbo witnessed a yearly celebration of Osun Osogbo festival which normally occurred along the river Osun. This annual event is always observed in August and is centered on the sacred grove of the river goddess called Osun. And this allows the flow of people from far and near to Osogbo. This event has gained the recognition of UNESCO [13].

The theory underpinning this study is Gravity Model. The model has been one of the most commonly applied models not only in transportation studies but also in other aspects of urban and regional analysis. Its applications cover such wide-ranging areas such as commodity movement, travelling, migration, household relocation and communication, among others [14], [15]. Such applications have usually been in an attempt to replicate or forecast actual interaction. The model is based on the Newton’s Law of Universal Gravitation which states that “two bodies in the universe attract each other in proportion to the product of their masses, and inversely to the square of distance between them” [14]. The work of [16] is the first adoption of the Newtonian Law to human interaction. The greater the number collected in a given space, the greater the attractive force there is. Gravitation, here as everywhere, follows the direct ratio of mass and the inverse ratio of distance. Thereafter, [17-19] applied varying versions of the gravity formulation to interaction; the first two to migration and the last two to retail sales. Also, [20] in a study utilized gravity parameters to explore the relationship between interaction patterns and regional development. It was later used to articulate and expose spatial inequalities in development in the study area. The model has been a focus of intense study for the past decades. The model can be mathematically stated as follows:

Iij=a.PiPj/dbij.

where Iij=volume of interaction between two places i and j.

dij=distance separating the two places i and j.

Pi=population of i.

Pj=Population of j.

a=constant of proportionality.

b=exponent of distance.

In the context of this study, the parameters of the model can further be interpreted thus:

Iij = the number of tourists coming to tourist centre j from settlement i.

dij = the distance between tourist centre j and settlement i.

pi = population size of settlement i.

pj = size of tourist centre j.

a = constant of proportionality.

b= exponent of distance.

The model has some empirical support which affirm that the number of people making a journey to a particular factory or shopping centre declines as the length of the trip increases; and that this decline is not usually uniform but rather, the fall-off or distance decay, is at first steep and then increasingly gently. This is because, for instance, people in one location, because of one reason or another, may possess greater interaction propensity than those in other locations.

This analogy is best based on [21] assertion that movement of goods, information and people within a social system, is an expression of his “principle of least effort” whereby inter community interaction is such as to minimize the total work of the system. In other words, it attempts to represent the potential interaction between any population point and all service points. The model therefore, will provide useful insight especially when combined with regression model (i.e. Gravity – regression model) in providing a framework that could be used in a hypothetico-deductive system to test hypotheses about human locational and spatial behavior for the use of tourist/recreational centres.

Table 1 presents the demographic Characteristics of the Osun Osogbo attendees. The percentage of male was (53.4%) and the female (46.6%). This indicated that both men and women were ably represented in the event. On the ages of the respondents, 25-34 years brackets formed (31.7%) of the total population. This shows that mid-ages respondents are also allowed to attend the festival. Meanwhile, ages 35- 54 years was (44.9%). This age brackets are those who are knowledgeable enough to give the significance of the festival.

They are also suitable for the study because such attendees within this age brackets are expected to have attained some level of stability in their homeland and which have resources for a returned trip back to their countries. Majority (67.2%) of the respondents were married and (71.4%) have at least secondary education. This indicated that the festival is for everyone and with or without educational background. About (84.7%) were business owners while (15.3%) were civil servant.

The respondent’s homeland was represented with (70.3%) of the respondents were from Osun State and Nigeria indigenes while (29.7%) were of foreign indigene. This shows that the festival attracted both foreign and indigenous participants. Oyeweso et al. [23] asserted that people from oversea countries such as Brazil, Cuba, the Dominican Republic, etc. come to Osogbo township to celebrate Osun Osogbo ancestral heritage annually.

Table 2 shows the responses of the attendees regarding the socio-economic impacts of Osun Osogbo festival. On the purchase of common commodity (91.0%) indicated the purchase of food, drinks, clothing, and local crafts. Other commodities that were commonly paid for were lodges (66.7%) and payment for transportation (71.5%). In other words, payment of these items invariably added to the economy of the local community. In line with the result [24], affirms that, ecotourism like Osun-Osogbo sacred grove and the annual festival contributed to the economic development to Nigeria’s tourism and travel industry including the host community. There are the large number of local and international attendees annually that have to pay for essential commodities during the visit.

On the social impact of the study, (67.2%) agreed that community engagement was enhanced, cultural appreciation (95.3%) and historical significance (86.3%). It was indicated also that, environmental awareness, especially it boosts sustainable tourism (89.4%), biodiversity conservation (95.3%), cultural ecosystem services (91.0%).

The health benefit/ therapeutic believe (93.6%) was indicated by majority of the respondents. Majority of the attendees believed that the Osun River has healing power and this was one of the reasons that make people attend this festival. It reflects the spiritual and therapeutic aspects of the Osun goddess's influence on wellness, fruitfulness, and societal harmony. This concurred with [9], that Osun Osogbo Festival serves as a sacred haven and a revered pilgrimage location for different people, who travel to seek solace, guidance, and solutions to their life's challenges.

Table 4 shows the responses of the hoteliers on the impacts of Osun Osogbo festival. On the economic impact derived during the festival, (85%) of the respondents were of the perspectives of increases in daily income, (50%) increase in the number of staff and (90%) indicated change of operating hours. The result was in line with [23] that Osun Osogbo annual festival boosts economy. This concurred with [25], that tourism enhanced employment opportunities for more than 235 million people throughout the world. Local creativity and innovation (63.3%) at the festive period also indicated economic impacts to the local people. This means that the businesses and patronage increased with the increase in the number of people at that particular time. The study also revealed that Osun tradition and culture (71.7%) were promoted. According to [26], Osun Osogbo Festival is about the grove’s spiritual, political, and religio-cultural essence of people of Yorubaland. It was further revealed that Osun Osogbo festival project the image of the State positively (81.6%). The respondents (60.0%) also agreed that there existed mutual understanding between the attendees and the indigene. About (81.7%) of the respondents were of the opinion that the festival leads to the improvement of cultural exchange.

On the environmental impacts, (83.4%) were of the opinion that historical sites and monuments were restored, (46.6%) of the improvement of aesthetics, and (75%) for creation of awareness and preservation of the environment. The result was in line with [27], that the event brings improvement in aesthetic design of the environment.

Promotion of mutual understanding between the attendees and the indigene 20.0 40.0 30.0 10.0 Improvement of positive cultural exchange 61.7 20.0 6.6 11.7 Environmental impact Restoration of historical sites and monuments 51.7 31.7 8.3 8.3 Improvement of the aesthetic nature of the city 18.3 28.3 48.3 5.0 Creation of awareness of environmental preservation & conservation 31.7 43.3 25.0 -

Note: SA means strongly agreed, A: means agreed, D: means disagreed, SD: means strongly disagreed.

Fig. 1 represents the perspective of the taxi drivers on the socio-economic contributions of Osun Osogbo festival. On the economic contributions, the result shows that (19.8%) of the respondents agreed to have change in operating hours, that is, the hours of working increased because of high patronage, increase in number of trip (22.1%), and (23.3%) increase in daily income. This result concurred with [28], that Osun Osogbo festival have significant economic benefits on the people and the communities around in the form of income, employment and local craft appreciation.

On the social impacts to the people and the communities at large, (16.3%) agreed on increased social interaction and (18.6%) on the environmental awareness. The finding of [29], supported the result of this study that the annual Osun Osogbo festival impacted tremendously on the socio-cultural aspects of the city of Osogbo. Evidence of the city's thriving entrepreneurial scene was on display as local artisans, including artists, fabric makers, painters, and craftspeople, exhibited their handmade goods and artifacts for sale, therefore, highlighting the diversity and creativity of the community's cottage industries.

Change in operating 18.60% hours 19.80% Increase in number of trips Inccrease in daily income 16.30% 22.10% Increase in social interaction Increase in environmental 23.30% awareness

The Osun Osogbo festival offers a unique opportunity for sustainable tourism development in Southwestern Nigeria. To achieve this, the following strategies are suggested: