Iszacc Bonnici, 19, was arrested at a Blue Haven home on Tuesday after police last December began and investigation into reports of a spate of graffiti on trains and railway infrastructure between Sydney and the Hunter Region.

Investigators searched the Central Coast home on Tuesday morning and took Mr Bonnici into custody after they seized items of interest including sketch pads, spray paint, a mobile phone, three cannabis plants in a hydroponic setup and 16 grams of dried marijuana.

Police said in a statement on Wednesday the items would be forensically examined.

Mr Bonnici faces 21 charges including seven counts of malicious damage, seven counts of entering and remaining on running lines, five counts of disguising himself with the intent to commit an indictable offence and one count each of possessing a prohibited drug and cultivating a prohibited plant.

Police allege the 19-year-old vandalised trains and railway infrastructure at Telarah, Hamilton, Maitland, Gosford, Campbeltown, Lidcombe and Kingsgrove.

They have also accused him of uploading images of the vandalism onto social media.

In Wyong Local Court on Wednesday, Magistrate Sharon Freund granted Mr Bonnici bail and adjourned the matter to August 12.

Among the conditions of his bail, Mr Bonnici must report to Wyong Police Station once a week, abide by a curfew between 8pm and 8am and not be in possession of spray cans or equipment used for graffiti.

He is also not allowed to enter any property belonging to the state's transit authority.

Mr Bonnici has not entered any pleas to the charges.

His arrest this week came after police charged a 35-year-old Newtown man earlier this month in relation to the alleged vandalism.

That man also remains before the courts.

Police said on Wednesday their investigation was ongoing.

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