Concerning Little Round Top, before Sickles and Meade on July 2, there was Hancock and Geary on the afternoon of July 1:
General Geary, after placing his division on the line of march from Two Taverns on the Baltimore turnpike, with two staff officers (one from the 109th Pennsylvania) rode rapidly ahead towards Gettysburg, and arrived at Cemetery Hill, where stood General Hancock in command of the troops then on the field, being the First and Eleventh Corps. General Geary dismounted and saluted General Hancock. General Hancock [asked], "General, where are your troops?" Geary replied that two brigades of his division were then advancing on the Baltimore turnpike. Hancock pointed to Little Round Top and said, "Do you see that knoll or hill? That is the key to this position, and if we can gain position on it before the enemy, we can form a line and fight a battle, but if the enemy secures it first, we will be compelled to fall back about seven miles to Pipe Creek. In the absence of General Slocum, I will order you to take possession of that hill." Geary turned to one of his staff [from the 109th], and gave [the necessary orders to secure Little Round Top]. (source: Pennsylvania at Gettysburg, address of Major Moses Veale, 109th Pennsylvania, September 11, 1889, 1:569)
The 147th Pennsylvania and 5th Ohio occupied Little Round Top, with the other regiments of the first and third brigades to their right (north), along with Knap's battery. It was not long before they observed troops marching north on the Emmitsburg road, which turned toward them and went into bivouac - the advance elements of Sickles' corps. Geary was relieved the following morning by the Third Corps.
[Incidentally, then Captain Moses Veale from the 109th Pennsylvania served on Geary's staff at Gettysburg as his assistant commissary of musters, and apparently he was one of the two staff officers who accompanied Geary to Cemetery Hill to meet with Hancock and recalled their conversation as above. Veale provides very minute detail with regard to other aspects of the battle, which bolsters confidence in his narrative.]