On the morning of June 9, 1898, the 1st U.S. Volunteer Cavalry Regiment, "The Rough Riders", disembarked from an empty coal train (approximately 1 mile east of here) joining 16,000 U.S. Army troops mobilizing in Port Tampa for the invasion of Cuba during the Spanish-American War.   Due to a shortage of transport ships and rapidly changing plans, Colonel Leonard Wood, Lieutenant Colonel Theodore Roosevelt, and a small group of cavalrymen quickly made their way to the port where they found a chaotic scene, making the orderly loading of troops, equipment, and supplies impossible.   Colonel Wood, identifying the empty S.S. Yucatan along the pier, immediately boarded it.    After securing the ship he tasked Lieutenant Colonel Roosevelt to bring up the regiment and its equipment on foot and board the Yucatan.   Once aboard, the Rough Riders were joined by four Companies of the 2nd U.S. Infantry Regiment.   Due to limited space on invasion fleet ships, almost half of the 30,000 U.S. Army troops in Tampa and approximately 200 Rough Riders were unable to embark, remaining in Tampa for the duration of the Cuban campaign.